Instead of checking into pub after bar after pub, show your friends you're not just a boozehound on Foursquare, but quite the literary creature on GetGlue's free iPhone app, which lets you "check-in" to whatever media you're consuming.
This can be a book, film, TV show or even music - with the updates being shared across Twitter and Facebook (if necessary). Instead of earning badges, you can earn stickers for the amount of check-ins you make, with various partners such as Warner Bros, Random House, Universal Pictures, Wired and so on offering up rewards.
As with Foursquare, it's believed these sort of apps have a big future, with even more partners jumping on board to offer incentives to visit their establishments or read/watch their media. I think it's worth pointing out though that it makes for a better experience for all if you don't share your updates across the various social networking sites. [iTunes via Mobile-Ent]