We had the same idea. Contest yeah good idea, bring traffic. And it brought a lawsuit. Last month we teamed up with another site. They ran a trivia contest and we supplied the prize. We each had increased traffic. The contest was very popular, hundreds of entries. We randomly selected a winner and mailed off the prize. Thought everything was ok. WRONG! A disgruntled contest entrant contacted his lawyer about the validity of the contest. To make a long story short, we were contacted by the lawyer and told we had to be able to provide detailed records of who entered the contest, we were told the questions were too subjective, the list goes on and on. We have currently taken the contest offline until we can do it legally. My advice; be careful, maybe contact a lawyer, expect the unexpected. Oh yeah the prize had a value of about $30. Shows you what some people will do.