If you subscribe to DirecTv and have a smart phone you may want to check out Viggle.com. Once you download the app you can “check in” while watching shows on certain channels. You also get additional points for watching the show and some shows offer bonus points. You earn points that can be redeemed for gift cards and other items.
I just downloaded the app last night. It may seem like it will take a long time to earn points but I have heard of others earning $20-$40 or so per month and if you are watching TV anyways.