Oh, I quite like the "slippery slope" one! I would imagine that most would be similar to the "repercussions" theme we had once, but we would also get a few literal ones (like your excellent recent story with alien ducks, heh).

I do think, though, that one-word noun themes work better for a comm that's inspiring fic, not reccing it. :)

So please do give us some more good ideas!