Just in case you didn't know, the new iTunes Radio has a channel called App Gamer that streams music from game soundtracks. There is some real good music on there, such as Superbrothers, Machinarium , Bastion , Waking Mars, Dropchord , Deus Ex , Street Fighter, GTA , etc. It's a great way to hear music from these games , as you don't have to buy any albums (unless you want to) and it keeps picking you new music from mostly well known games.
