Also in this space are LendingClub, who don't do auctions but have a similar model of letting people buy portions of other people's loans. They claim an effecti

Also in this space are LendingClub, who don't do auctions but have a similar model of letting people buy portions of other people's loans. They claim an effective APY of just under 10%; I've invested a (very small) sum with them as an experiment and so far am on track to hit that APY (after 2 months).