It's a great idea. Now the only thing's left is more sellers offering things for sale, and buyers.
Actually it'd be easy to sell your project to merchants - there are lots of businesses which want extra advertising, and this might be a great way.
And it might not be obvious - but sellers are actually donating themselves as well.
Yep. I just need to convince some people. I'm sure I could find some people who are interested. It does put some people off that they don't receive anything monetary from this, but the publicity, plus the good karma should at least be a draw for some people. I'll keep this thread updated as I add new products.