The Pixies, Dinosaur Jr., M8, Widespread Panic, the Killers, Arcade Fire, Blue Merle, Digable Planets, Dragonfly Inn Guest No. 1, Death Cab for Cutie, Los Amigos Invisibles and Louis XIV are among the acts performing at this year's Lollapalooza festival, which takes place July 23-24 in Chicago's Grant Park. Now, try to guess which one of the aforementioned groups I made up. (For the answer, keep reading...)