Let's face it: Spinoffs usually suck. Joey isn't funny without his friends, Frasier was just a pompous ass outside the bar and, for all the hype, Joanie really didn't love Chachi all that much. In music, however, there are two bands that get it exactly right. Sparta and the Mars Volta -- the bastard children of postpunk powerhouse At the Drive-In -- make for perfect musical brethren. On the one hand, there's the Mars Volta -- the smarmy, know-it-all favorites of the über-elitist scene. But whereas that group may be the Marcia Brady of rock, Sparta has quietly taken the role of Jan -- a little less noticed, a little more whiny, but still a knockout after maturing a little. Comparing the tortured, angst-ridden sounds of Sparta to the middle Brady girl (and, in the process, describing a child actress as hot) may be a little twisted, but the band has held up its end of the sibling rivalry with two fantastic full-length albums and a scorching live show.