Valve has made a 22-song soundtrack for Portal 2 available via its website, and it's free for all to download right now.
It's the first of three albums, or "aural stimulus packages" as the Aperture Science refers to them, and features tracks with comedy song names such as 'I saw a deer today', 'concentration enhancing menu initialiser' and 'Comedy = tragedy + time'.
It features a mix of intense mechanical electro beats, none of which we could hum if asked and none destined to become a gaming culture icon like the 'Still Alive' song from Portal 1, but they certainly bring back the memories of playing through Valve's recent masterpiece.
There are also a bunch of ringtones on Valve's music page for use with iPhones and Android sets. Head through the source link for everything.
For any Valve fans that missed it, be sure to check out this interview with Valve programmer Jeep Barnett in which we discuss Portal 2, Steamworks, Left 4 Dead PS3 and groundbreaking tech.