Hey, check it out. Free music. Specifically, a free soundtrack to Portal 2. More specifically, Valve is offering the complete 64-track soundtrack to Portal 2, “Music to Test By,” for free on the Portal web site.

The Portal 2 soundtrack, like every other aspect of the game, was excellent, with some haunting and tense music that reflected both the dark humor and the surreal, clever action of the game’s various Aperture Science settings. It had some great electronic and ambient tracks, and listening to any of them will take you back to the shifting walls and grimy pipes of the testing facility. For the record, the two catchy sounds in the Portal 2 commercials are “Science is Fun” and “Halls of Science,” both of which are in the soundtrack.

Valve also released a handful of ringtones from the soundtrack and the game’s sound effects. There aren’t any quotes from GLADoS, Cave Johnson, or Wheatley, but there are portal and button sounds, plus short clips of the more notable tracks in the soundtrack cut for ringtone use. If that’s not enough, Valve is also releasing the “Peer Review” DLC for Portal 2 Wednesday. It’s free and mostly co-op but with some single-player support. Keep an eye out for it on Steam.