Even though I watch much more TV than I should, I haven't really gotten into the whole "check-in" aspect of it yet.
With Viggle, you can check in to programs, get points and redeem them for "rewards," which include everything from Starbucks gift cards to movie tickets. So far the site has more than 250,000 registered users.
If you don't mind sharing your guilty pleasures, you may want to try the app. It's available in the iTunes store (for free) and is coming to Android soon.