Portal 2 - home of obtuse physics puzzles, dark humour, delicious confectionery and root vegetable power sources - is set to have its first round of post-release Downloadable Content (DLC) released on Wednesday the 5th October (yes, of this year) and it should be free. Free, that is, so long as you already have the game of course. Portal 2 Peer Review sees new co-op missions for our robotic friends Atlas and Peabody and a challenge mode for all maps. The DLC should be downloaded automatically via your Steam client.
Complementing this release nicely, the Official Portal 2 Website have uploaded 24 more Portal-based tracks with "Songs To Test By - Volume 3". You can download this soundtrack - and the other two Volumes - as a .zip for for free by following this link to the Portal 2 music mini-site.