Fifteen years after his first Lollapalooza festival, founder Perry Farrell's vision is more rosy than rebellious. "It's about coming here as a creative force to celebrate beauty, nature, harmony, peace, and freedom," he said backstage in Chicago on Saturday. Looking dapper in Marc Jacobs slacks and a J. Lindeberg vest, the former Jane's Addiction frontman was getting ready to introduce Wolfmother, one of 130 bands on an all-inclusive playbill Farrell concocted for the three-day, only-in-the-Windy-City concert. A few feet away, his toddler son, Izzadore Bravo, was playing his ABC's on a pint-size guitar. "See, this is what I'm talking about. Good job, Izzadore!"

Meanwhile, groups such as Wilco, Of Montreal, and Living Things made the press rounds, and Jared Leto, in head-to-toe black and smudgy eyeliner, kicked back with his post-grunge band, 30 Seconds to Mars. But the real action, of course, was on Grant Park's eight stages, where the guitar licks of the Raconteurs and Editors, and hip-hop beats of Lady Sovereign and Common, kept over 70,000 fans entertained.

Hometown favorite and Saturday's headliner Kanye West hit a surly patch when his sound system malfunctioned. "I'm taking this tour around the world, and my own city can't get it right," he fumed. But all was forgotten a few moments later when his smash, "Gold Digger," blared from the speakers. Anthony Kiedis of the Red Hot Chili Peppers, who headlined the 1992 Lollapalooza tour, was in a mellower mood. After performing the band's new hit, "Dani California," the Angeleno noted: "That song is about the dirt we hail from. But it's pretty great here, too."

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— Sarah Cristobal