Pledge Bank: I'll do it but only if you help

Pledge Bank is a site to help people get things done, especially things that require several people. PledgeBank allows users to set up pledges and then encourages other people to sign up to them. A pledge is a statement of the form 'I will do something, if a certain number of people will help me do it'. The creator of the pledge then publicises their pledge and encourages people to sign up. Two outcomes are possible – either the pledge fails to get enough subscribers before it expires (in which case, we contact everyone and tell them 'better luck next time'), or, the better possibility, the pledge attracts enough people that they are all sent a message saying 'Well done—now get going!'

Typical pledges: "I will Go Vegetarian between 25th - 29th June 2008 but only if 15 other meat eaters will do the same."

or: "I will pledge to help the Anderson Animal Shelter but only if 10 other local people will do the same."

Great idea and it seems to be working!