This site IS all free, but you need an invite to join. Its called Lockerz. It can take a while, or as soon as a week to redeem prizes. It IS real, I saved up for Modern Warfare 2, and they actually delivered it to me.
Use it as a regular 1-2 minute thing if you want, because you get 2 points for logging in daily and 2 points for answering a daily question. Its so fast and simple, and within a month you will get to 400 points easy, which is the amount of a brand new game.
Anyways, I'm here to invite any of you who want to try it, so just leave me your email addresses and I will invite you. GOOD LUCK TO ALL OF YOU!