I love the creativity, though I have to admit, I'm a little confused.
YC already does a great job of releasing great startup ideas (see links below in the off chance that you haven't read them already). And it seems like everyone I met who got in was accepted because of the awesome things they created. So if you're short on ideas, read the lists, and then get to work and have something to show for it by application time! Whether or not you get in will probably matter less and less once you're cranking away at a company you're really into.