There’s few better ways to extend the capabilities of your Apple TV 2 than installing XBMC on it, but after the latest Apple TV 5.2 software (iOS 6.1) dropped, there was just no way to do it. Thankfully, XMBC has been updated, and will now stably supercharge your second-gen Apple TV just as well as it did before.
To do the install, it’s as simple as following the instructions over on the XBMC wiki. It’s pretty easy, although it does require some command line delving and a reboot. Power through all of that, though, and you’ll have an incredible, open-source media center running on your Apple TV 2 that can play pretty much anything. Nifty.
Source: XBMC