High up on Maslow's hierarchy of needs are the 'Esteem Needs', which Wikipedia defines as: "where the individual will desire a sense of competence, recognition of achievement by peers, and respect from others".
I'd express this slightly differently as the very human desire to show off how cool we are. And focusing on this is a good way to kick start a successful community.
So I'd argue that the motor behind blip.fm is the desire to show what great musical taste you have - or even what a cool DJ you can be.
And Herman Miller's new site thoughtpile.org is kind of a take on Yahoo! Answers, but with more of a social conscience - and it does look lovely in a kind of gloopy new age way. You get the chance to show off your genius thoughts - and change the world at the same time. And that would kind of boost your self-esteem I guess!
I think it's thoughtpile.org ...
You're right - all fixed now!!