SANTA MONICA, Calif. -- Microsoft opened with "five Halo fans from Libertyville, Illinois." These apparently amateur musicians heard the music of the game "and heard rock," according to Peter Moore, Xbox boss.

The band took its instruments as the movie screen lit up with a star scape. The amphitheater was lit in blue and the band began to play. A lead violinist with '80s hair started rocking out. The screen shows dozens of shots from "Halo 3," due out in September. The crowd cheered.

Moore says they're about to unveil "the biggest lineup in video game history."