[easy_rider]

Yes this. Actually the first time I came across a (variation of) this idea, it was years ago and brought up by a co-worker. I have been tinkering with the idea, and also came to the same conclusion, that virality / marketing in general were probably going to play the part hugely, as like you've stated, this has been done a lot..

Maybe it's something that people do not want.

I could see this having great potential in the dating/flirt sectors obvously ;) But you could also imagine things like "shit I think I left my jacket at x/y, anyone found it? " at a festival. Anonimity would probably be mandatory for success.

Remember how well Latitude faired?