Anyone ever do an idea like the following:

[Rictor]

Sounds like a scam doomed to failure or worse.

You're better off letting people enter a contest like that for free and encouraging them to send their friends to vote for them. Word of mouth will spread and you will make good cash from your amateur advertisements that you put all over the site.

Then you can offer a small weekly prize ($25 gift certificate, a free month to a porn site, a dvd, whatever) or a big annual prize. Stay away from cash and talk to your lawyer for the legalities of holding contests like this.