Ripple Payment System
Ripple is an interesting attempt to create an open, decentralised monetary system. The idea is to route payment from Alice to Bob (who don’t actually know one another) via any number of intermediaries whom they know, or who know one another. E.g. Alice might pay Charlie (whom she knows) $20, who then pays Bob (whom Charlie knows). It’s based on credit: each person grants people he knows a certain amount of credit, and thus a payment can move through the system. Essentially, it’s the international banking system made available to anyone. A really cool idea.
