Trade it on Trodo

Written by Adrian Holovaty on December 9, 2002

I'm back from my moving-time hiatus to bring you a special announcement. (And Lawrence, Kan., is a great town -- thanks to those who've e-mailed.)

I've spent the last few months working on a side project in my dwindling free time. Today, I'm happy to announce it has launched. is kind of an online bartering site. Basically, you register for a free account and list items you're willing to trade -- CDs, DVDs, books, video games, video tapes or vinyl records. When somebody requests an item from you, you pay for the shipping, send it, and get a credit in that category. Then you can use your credits to request items from other people -- for free.

When you register, you get three free credits. After that, you get a credit for each item you ship successfully. (The credit is awarded after the "buyer" gives you feedback.)

John Rhodes of WebWord had the idea; I was the humble programmer. We both kind of played around with the design (which is incredibly plain at the moment).

Check out the site and let me or John know what you think, or how it can be improved.


Posted by Aaron Schaap on December 9, 2002, at 7:03 p.m.:

First of all the idea is awesome. Good job on working on such a project.

Not a HUGE fan of the design but it all comes in time. The biggest point is that it's up and working :-)

One thing:

On the register page ( - it's rather long. I would have it sectioned into "Steps" STEP 1 > STEP 2 > STEP 3

STEP 1: Contact information

STEP 2: Enter items you're willing to trade

STEP 3: ONLY if someone would like to add more than one item.

STEP 4: This is what you have input. Is this correct?

STEP 5: An email has been sent to you at

Just an idea.

Posted by Nathan on December 9, 2002, at 11:38 p.m.:

The influence of Adrian's subconscious is on that registration page: "Short Description: (Required.) Example: 'Beatles Abbey Road CD' "

Posted by Gina Setser on December 10, 2002, at 4:34 a.m.:


You might consider allowing people to register who have nothing to trade yet. They might just want to browse the offering first. Just a thought.

Posted by Adrian on December 10, 2002, at 7:40 a.m.:

Thanks for the comments! And yes, Nathan, rumor has it I am a Beatles fan. ;-)

Clearing up a few things...

Having registration on one page was a business decision, and I don't know whether that will change any time soon. I originally programmed it to span three pages, but we decided that was more trouble than it was worth.

Also, anybody can browse or search the available items; you don't have to register just to browse.

Posted by Lou on December 10, 2002, at 5:56 p.m.:

I see that you have allowances for 3 items to be listed as ready for trade, however a user may have only 1 or as many as several dozen items they are ready to list. Rather than having them navigate several pages to list multiple items, or scroll past "dead" forms, why not make use of the DOM to allow mutiple iterations of the same form to be generated on the fly at the user's request: "List another item".

Its a good idea, but I'm a bit confused by the decision to make the trader pay for shipping (essentially paying someone to take their items) rather than making the buyer pay - via paypal for example. There's an inherent exposure to risk, would you be so kind to explain the business reasoning behind that? I would appreciate it, and best of luck with the site.

Posted by Lou on December 10, 2002, at 9:40 p.m.:

I went back to the PPK article on Evolt to review the code used to create replicate forms, and realized why it shouldn't be done yet (bad browser support in even the latest browsers. That's a real shame.

Posted by John S. Rhodes on December 10, 2002, at 10:16 p.m.:


Great comments! Here are some thoughts...

Our economic model doesn't deal with money. It is quid pro quo and it isn't based on financial transactions. Being quid pro quo means that there is always a "this for that" exchange between members. You make a request and give up one credit. I receive your request and ship the item. You get the item and leave me feedback. I get the credit once you have given me that feedback. There is a constant give and take. Both sides must work with each other during the transaction. There is continuous push and pull to make the transaction happen. Credits move smoothly, no money needs to change hands, feedback is relevant, and trust is built via communication.

There is one other little caveat here. The Shipping Information area that Trodo members use indicates that you should enter where you are willing to ship the item. There is no policy (at this time) that indicates that you *shouldn't* ask another person to carry the cost. For example, I might say that I am willing to ship any place in the U.S. but it will cost $7.50 to ship to Europe or Asia. That is entirely fair. Trodo is about facilitating transactions, no controlling them. Of course, in general, I think it is foolish to try to extract money for shipping. Members will route around that difficulty by not asking for the item. Keep in mind that when Trodo gets larger, there will actually be competition to give away items! You earn credits by giving items away. If you erect barriers to this, well, you do so at the risk of not being able to unload items. You hinder the quid pro quo process built into the Trodo economic model.

If other folks have other questions about how Trodo works and why we made certain decisions, fire away! I love answering these questions because I like to have my business assumptions reviewed and analyzed. Keep in mind that I spent a lot of time thinking about how the system should work. No "economic" decisions were made without serious thought. In fact, I worked with a mathematician on testing and modeling the system. So really, ask more questions. The site is deceptively simple. How it works is actually very complex and hard to grasp when you start to dig into it. But, like I said, I enjoy the challenge.

Speaking of challenges, I would like to ask for some help. How do you think we should market Trodo? What will it take to get you to sign up? How can we get other people to sign up? Can you help us spread the word on Trodo? What incentives can we offer? What do you think of the "Get a FREE item when someone signs up under you!" referral system? We are definitely in marketing mode now and I would love to hear your suggestions.

Posted by Robin Sloan on December 11, 2002, at 12:58 a.m.:

Nice work on Trodo, Adrian and John. My question: What will make people want to use Trodo credits as a unit of exchange instead of, say, dollars? As I explored the site, these are the kinds of questions I asked myself: "What if I think my CD is worth 2 credits? Or just a half credit? Or what if I decide what I really want is a DVD, and all I have is CD credits?" These are all transactions that money is well-equipped to handle.

So, what's the Trodo advantage?

Posted by Lou on December 11, 2002, at 2:37 a.m.:

Thanks for the response John. I'm quite intrigued by the whole concept, but I'm a bit concerned about the reliance of the network on trust. How does one prevent the system - or more specifically and of, perhaps, of more concern a single user - from falling prey to a scammer with free credits who signs up just to snag a few items for free? Certainly the malicious user will not receive any additional credits and be excluded, but could they re-instance themselves under a different user name, or with a different email address? And how willing are most people to trade with others of "untested trust"? Again, I appreciate any insight - and best of luck with this endeavor.

Posted by kpaul on December 11, 2002, at 6:57 a.m.:

Nice site. Reminded me of (which became in 2000 sometime, and which now just redirects to hadn't checked on the site since it was ages ago.)

I'd met one of the people originally involved with it at the AZ Republic in Phx just before he quit to join swaprat.

In any case, best of luck with the site. It's a good idea.

Posted by kpaul on December 11, 2002, at 7:11 a.m.:

some more thoughts that came to me. if i remember corrently, swaprat charged a dollar 'transaction fee' for each 'swap.' i also think they gave new members a $5 credit or something like PayPal did/does. there may be articles out there on any business models they had. i haven't looked yet. if nothing else, the info might be useful as what not to do as they're not around anymore. :)

although to their credit maybe the web in '99 wasn't ready for the idea. might be an interesting article in what happened to them, though...

Posted by Gene on December 11, 2002, at 8:21 a.m.:

Great site. It reminds me of an old SNL skit about the change bank.

"All the time, our customers ask us, "How do you make money doing this?" The answer is simple: Volume. That's what we do."

Posted by David Wertheimer on December 11, 2002, at 6:53 p.m.:

"Volume." Great point, Gene.

I think this idea may stick precisely because it is free. I was a regular until low-budget commercial enterprises kept undercutting me; I don't get sales inquiries anymore. At a cost of $0 the social model returns. Of course, that doesn't explain how Adrian and John will pay for it once the bandwidth gets hot.

One request I have is just that: a request list. If I want "Abbey Road" and I don't see it, I'm SOL. Why not make two piles, Available Items and Wanted Items?

Posted by Lou on December 11, 2002, at 7:11 p.m.:

One last question - and I appreciate the answers already provided, they are quite informative. Can users swap other types of credits for goods? For instance, if I want a DVD but I only have CDs to swap am I out of luck or can the trader say, I'll take this for 1 DVD credit or 3 CD credits? That would seem to strongly reenforce the bartering system

Thanks again.

Posted by Randy on December 12, 2002, at 1:44 a.m.:

Yes, Lawrence is a great town. I lived there for many years. Too bad the job (tech) selection is so bad, unless you want to work in a restaurant or construction. We will be heading back that way after we finish our stay on the other, empty side of Kansas. (Hays)

The sounds like a great idea. Good luck.

Posted by anonymous on December 12, 2002, at 7:49 a.m.:

David Wertheimer wrote: "At a cost of $0 the social model returns. Of course, that doesn't explain how Adrian and John will pay for it once the bandwidth gets hot."

David, we are investigating this. There are several obvious models. For example, we could charge $0.10 per transaction. Or, perhaps we charge a low yearly fee, something between $8-15 perhaps. Good question!

David also wrote: "One request I have is just that: a request list. If I want "Abbey Road" and I don't see it, I'm SOL. Why not make two piles, Available Items and Wanted Items?"

David, I don't want to dive into the economic model here, but the core of your idea is spot on the mark. It would be good to have an area where people could see what other people wanted, easily and effectively. Furthermore, Trodo member profiles could have more information, so people could "connect" more easily.

Lou wrote: "Can users swap other types of credits for goods? For instance, if I want a DVD but I only have CDs to swap am I out of luck or can the trader say, I'll take this for 1 DVD credit or 3 CD credits? That would seem to strongly reenforce the bartering system"

Lou, there are no current plans to offer this kind of exchange. There really are some good reasons for why we *don't* allow this. It would take many words to describe. However, I will hint at it with this. If we allowed users to transfer credits too easily, then it would be easy to "bomb" a cheaper category (e.g., load old paperback books when registering), but then transfer those credits to Playstation 2 games. In my (our?) opinion, the items are not of equal value. We want to keep it one to one in the category for this reason. (That's the short explanation; left out many details.)

I've been toying with the idea of offering up a "trading space" or something like that, where users could exchange credits with each other, but not directly with the system. So, maybe I could trade of my two VCR credits for one of your DVD credits. This is *not* as simple as it sounds. Technically, it is a bit complicated, but more importantly, it is disruptive to the Trodo economy more than people might realize. Trust me on that!

My final comment is that Trodo really isn't a barter system. Sure, it is easy to say that Trodo is a barter system, but it really isn't. Barter systems are synchronous (we agree to swap at the same time) and person-to-person (you are agree to trade with me, I agree to trade with you). Trodo is an asynchronous, person-to-network economy. Take some time to wrap your brain around that. It is a good time... ;-)

Posted by Lou on December 12, 2002, at 9:13 p.m.:

Wow and thanks. I really appreciate the time you've taken to answer everything here.

Posted by Micah on December 13, 2002, at 9:41 a.m.:

This sounds like a pretty good idea. I've got my eye on a certain CD, but I've put off registering until I can ask some questions.

Two questions. Is it possible for somebody to create two accounts and send stuff back and forth to himself, building up insane credits? Also, why do you need my mailing address when I try to register?

Finally, it would be nice if users had the option sort items alphabetically. If I'm looking for CDs by my favorite bands, that would help.

Posted by John S. Rhodes on December 15, 2002, at 1:36 a.m.:

Micah wrote: "Is it possible for somebody to create two accounts and send stuff back and forth to himself, building up insane credits?"

If you think about this, it is difficult. When someone registers, they enter three items that they are willing to give away and we "give" them three credits. If they add additional items to the system, they don't earn credits. Now, suppose a friend signs up, adds three items and we "give" them three credits. Person A has three Trodo credits and Person B has three Trodo credits. Person A might request all three items from Person B. In doing this, Person A uses up their three credits but Person B will now have 6 credits. That's about as far as it can go. Those credits move, but they can't really accumulate very easily. There are ways to cheat to get around this, but it would take effort. I'm obviously not going to explain how to cheat here because I wouldn't want to make it easy for people. But yes, it is possible to cheat, but it isn't that easy and we are watching very closely for this kind of activity. At some point, we will might limit the number of credits a person can have and perhaps the number of credits they can use in one day. There are other ways to catch this that I'd rather not detail here; trust me, we *are* watching for cheating.

Micah also wrote: "Also, why do you need my mailing address when I try to register?"

There are a few reasons for this. First, we use this information to verify that a person is a real person. Along these lines, if necessary, we can check one Trodo account against another Trodo account to see if that person is trying to enter bogus information (e.g., duplicate account). Second, if there is a dispute of some sort, we can use this information to contact the users. And, if the Trodo member's email stops working, we have a way to contact them. Finally, if we ever need to send something to Trodo members by postal mail, we will have addresses available. It goes without saying that we will *NEVER* give this information away. It is stricitly for use by Trodo. Of course, we realize that we need to write up a Privacy Statement to cover this. I apologize to everyone for not having that done already!

Micah wrote: "Finally, it would be nice if users had the option sort items alphabetically. If I'm looking for CDs by my favorite bands, that would help."

Good idea. I'm not entirely sure where that falls on the priority list right now but it is great feedback. Baby steps! ;-)

Posted by John S. Rhodes on December 30, 2002, at 10:10 p.m.:

For those folks that care, I wrote an article explaining more about Trodo.

Trade it on Trodo: Understanding and Improving Barter

Summary: The first purpose of this article is to provide a brief summarization of how barter works. The second purpose is to explain how Trodo capitalizes on the strengths of barter while minimizing its problems. The final purpose is to give readers a clear idea about how Trodo works, including the philosophy behind it.

Posted by YOUNG_LINK_ on October 6, 2005, at 1:21 a.m.:

The site is currently down. It says it's been "suspended".

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