Some of you may know that I have roots in a community called Planetwork that has had an interest in 'alternative' currency and the role that digital identity could play a role in a emergent currency systems.

So, today my interest was peaked by this e-mail from Biz Stone at Twitter talking about an interesting new application being built on twitter.

Do You Owe Someone A Beer?

Foamee.com is a fun IOU system built on Twitter that helps you track who you owe beers to (and vice versa). All you have to do is follow the account "ioubeer" and then send it @replies. So, say you owe me a beer for helping you change a flat tire, this is what you'd send to Twitter:

@ioubeer @biz for helping me change that flat tire

Then, your IOU will show up on the front page at foamee.com. There's even a way to tell it when that beer has been redeemed. I think a root beer version is in the works. Maybe even a latte version? Those are foamy too. Dan Cederholm of SimpleBits design is the mastermind behind this fanciful creation. We think it's really cool. Thanks Dan, we owe you a frosty one!

Visit: http://foamee.com
Follow: http://twitter.com/ioubeer
More: http://simplebits.com