Tom Morello, Serj Tankian, Ben Harper, Billy Bragg and others joined forces to sow some musical seeds of revolution last night (March 13) at South by Southwest in Austin, Texas.

The musicians were celebrating the release of "Body of War," the new documentary about paralyzed Iraq war veteran Tomas Young, who also worked with Pearl Jam's Eddie Vedder to curate the film's soundtrack. Vedder was caring for an ailing relative and unable to make yesterday's premiere of the film and concert, but the others filled in admirably.

Bragg previewed three songs -- "Farm Boy," "Oh Freedom" and "Sing Them Back Home" -- from his upcoming album, "Mr. Love and Justice." New Warner Bros. signing American Bag performed "Home Mr. President," a song it wrote especially for the occasion. Tankian performed a solo set on piano, while Morello and Harper joined forces for the latter's "Gather 'Round the Stone."

The outspoken Morello, railing -- as is his wont -- against "an awful (presidential) administration and its awful war," -- then played a Nightwatchman set that included "Flesh Shapes the Day," Rage Against the Machine's "Guerrilla Radio," "Battle Hymns" (his contribution to the "Body of War: Songs That Inspired an Iraq Veteran" album), "House Gone Up in Flames" and a rendition of Woody Guthrie's "This Land is Your Land" which included the often deleted final verse and found Morello trading verses with Bragg, Tankian and Mason Jennings.

Kimya Dawson closed the show with a three-song set -- including the "Juno" hit "Anyone Else But You," and some pointed political commentary of her own.

The "Body of War" album is due out Tuesday (March 18), while the film is rolling out on a staggered schedule across the U.S. Proceeds from the album sales will benefit the non-profit Iraq Veterans Against the War.