tangor - 4:47 pm on Dec 6, 2010 (gmt 0)
Polls, essays, etc. have been around for a while. The coding and set up of those is not the problem, dealing with legal issues in various jurisdictions which govern contests, lotteries, etc. is where the most work is required. I'm not a lawyer, but I do suggest you talk to one if your contest(s) in any way deal with tangible prizes, money, or inducements.