Information about past, current, and any future contests that come up. And if it get's populer enough, make a message board where any one wants to can announce contests there and talk about current/past/future contests.
I tried my own
little SEO contest over the last three months on a video game message board to get the members to link bomb there wiki page, and even with Google crawling the pages, they didn't even get indexed yet. (
PR 5 domain) Today the contest ended. Hopefully with SEOs and not teenager/video game fans trying to get indexed, we'll be indexed in time!!!!