Opening the microlending system
Soni Pitts points us to Kiva. The idea seems to be that anyone can be a microlender... Instead of spending $25 on lattes, you can help a farmer in Bangladesh buy a bull... and then he pays you back.
This is one of a number of cool ways to do first world wealth transfer. The challenge, as always, is in the execution. There's not a huge shortage of money for microlending operations--there's a shortage of great banks, great people to run those banks and access to the right sort of people to make the loans to.
It's easy to imagine that every culture is as crisp as ours when it comes to money. (and hey, we're not even that good at it... just look at credit card debt for an example). Most of the challenge of microbanking is in changing social systems, not in moving the $25. But like all things on the net, this is a great first step in opening up bottlenecks.