If you can't get enough of Portal 2's ambient soundtrack, Valve has made a collection of tracks available on its site as a free direct download.

The 22-track "Songs to Test By" album is not a complete soundtrack (the ending theme isn't included, in case you're wondering), but it's certainly a more reasonable alternative to downloading the unofficial Portal 2 audio rip, which is said to contain more than 200 individual files. It turns out that there's a lot of music in Portal 2!

Also available at Valve's site are a selection of iPhone- and Android-compatible ringtones, including a version of the excellent "Turret Wife Serenade."