I heard about this a while ago (possibly even on the SDMB originally), but I’m having trouble finding it via searching (all the obvious terms I can think of end up being about how to secure financing for a startup).
The idea was that you’d have a network of people that you trust enough to loan them money. So, instead of using money to pay for something within network, as long as you had people who trusted you (and you hadn’t exhausted whatever debt was available) you’d just transfer a debt to them and it would all work out. Any time you needed to pull real cash out of the system, you could go to your neighbors in the graph and ask for real cash.
Anyone know what I’m talking about? They had a very web 2.0 website with a video explaining it. I was talking to a friend about the concept recently but I couldn’t find this site to reference.