Wish I thought of it

Take a look at dotprodomains.com.

Sustainable? Who knows... Effective? Profitable? Genius? Probably.

Link courtesy of Seth Godin. From the same post I also found another stupidly simple idea I like to think I wish I'd had, but know in reality I would never have done anything with, Woot.com. Seems like it's been around for a while, can't believe I hadn't seen it before.