Valve announced that the critically acclaimed indie band The National is contributing a brand new song for Portal 2.

"The inclusion of the original song, 'Still Alive,' in the first Portal game was part of what made the game special," said Valve writer Chet Faliszek in a press release. "For Portal 2, we wanted to extend the use of music. When Bug Music mentioned to us that The National might be interested, we jumped at the opportunity to work with them."

Like the popular Jonathon Coulton song from the first game, The National's track will likely tie directly with the game's theme. Known for it brooding lyrics and austere song arrangements, the band's vibe should mesh well with GLaDOS, who I'm sure would enjoy the song "Terrible Love" and sing along with the "'cause I'm evil" chorus in "Conversation 16."

The National's latest album, High Violet, debuted at #3 on the Billboard charts last May, and the Brooklyn via Cincinnati band has been touring nonstop around the world ever since.

You can learn more about the band on its website, and check out their music on MySpace. "Fake Empire" is a good entry point for newcomers.

Portal 2 hits store shelves and Steam on April 18.