Most videos of the Tetris remix contain a musician playing on an instrument or actual gameplay footage with the song playing in the background.
People who purchased their ticket for Twilight through Fandango received a special code to download an exclusive remix of the Carter Burwell song Bella's Lullaby.
VGMix - The second popular site for video game music, VGMix features a large collection (maybe even larger than OC Remix) of songs free for downloading.
You'll find many songs released under the Free Music distribution philosophy, meaning you can download, remix and distribute the songs as you like.
midnight Juggernauts - 45 & Rising (Cut Copy Remix) 13.