Valve is making the Portal 2 soundtrack available for free via the game's website.
Song To Test By will be released in three volumes, the first of which, featuring 22 tracks, is up for download now.
There are also a number of ringtones up for grabs on the site.
"Whether you're a mega-science corporation with decades of test experience, or a young start-up liberating your first test subject from non-testing with a chloroform-soaked rag, Aperture guarantees results," read a blog post on Thinkwithportals.
"Wake up your test subject, open the chamber door, and press play - let Aperture's patent-pending rhythmic compliance enhancers do the rest."
Alas, "Still Alive" writer Jonathan Coulton's contribution doesn't feature in Volume One. Here's hoping "Want You Gone" pops up in Volume Two.