Check out the relatively new website called Prosper.com. It is a peer-to-peer lendingplatform that focuses mostly in the US. It follows on the heels of Zopa, which started in the UK.Prosper has sophisticated credit rating tools and interest rates vary depending on supply, demand, and credit risk.
The nice thing about Prosper is the community element. As the site notes:
"Groups are the heart of the Prosper marketplace. A group is organized by a single leader and consists of borrowers who all share something in common. Borrowers request membership or are invited to join a group, and since membership is limited, usually have some connection with one or more group members."