CHICAGO -- Somewhere in Chicago on Friday night, hopefully dry and warm, you can bet that Perry Farrell was grinning ear-to-ear. Despite a persistent all-day rain that turned the massive Lollapalooza fairground along the Chicago waterfront into a slippery mudbog worthy of Woodstock, the musical mash-up spirit that the festival's co-founder has been chasing for nearly 20 years made a strong showing.

As the rain finally let up in time for the headliners to take the stage, on the north end, the battling band of brothers (and cousin) [artist id="1233888"]Kings Of Leon[/artist] were making the most of their third go-round at the fest, pumping out their muscular Southern boogie to an adoring sea of fans. Meanwhile, at the other end, British synth pop veterans [artist id="1057"]Depeche Mode[/artist] moved muddy feet with a classic set of keyboard anthems, including "Enjoy the Silence" and thunderous set-closer "Personal Jesus."

But it was what was happening in between the two stages that surely made Farrell smile. The [artist id="702"]Jane's Addiction[/artist] frontman, who has long harbored a fascination with techo/rave dance culture, expanded his dance area this year and created a party space that drew huge crowds all day. Despite two world-famous headliners performing just yards away in either direction, the large leafy area was packed with thousands of bodies gyrating and throwing their hands in the air ecstatically to thumping techno, just as they had earlier in the day to jeep beat hip-hop and old school dance tunes.

However, that's not what the whole day was like. With one of the weaker first-day line-ups in the reborn festival's recent history, the day began slowly in a steady drizzle with California's the Henry Clay People warming up a sparse crowd with shambling indie-rock tunes about the apocalypse and a story about an urn of a late friend's ashes they are touring with. Matching the grey drizzle perfectly on an adjacent stage was were pastoral, beardy plaints of the Other Lives.

Atlanta's Manchester Orchestra brought none of those daffodil vibes, though, crunching bones with driving rockers like "In My Teeth," "Shake It Out" and their breakthrough hit, "I've Got Friends." They ended with the surging/swooning epic "Everything To Nothing" just as the rain really began to fall.

Once the skies opened up around midday -- and all those brightly colored mohawks began to sag and the lunchtime beers became a terrible idea -- the soggy masses had New Brunswick, New Jersey's Gaslight Anthem to keep their spirits up. Channeling an inked-up Springsteen, singer Brian Fallon wove his stirring tales of busted hearts and small town girls with their sailor tattoos with a charming grit, strumming hard through get-outta-this-town anthems like "Great Expectations," "The '59 Sound" and "Old White Lincoln."

The Knux, one of the few hip-hop acts on this year's bill, made sure their presence was known, hitting the stage to the strains of the Kinks' "You Really Got Me," and swaggering like a rebel rock band, complete with distorted guitars over sampled beats. Clad in matching black Knux T-shirts, they looked like a rap Ramones tribute. MC Krispy Kreme did his best to get the crowd hyped with shout-along choruses on "Remind Me In 3 Days" and the rousing "Cappuccino."

Cleveland's Kid Cudi fit surprisingly nicely on the Perry Stage after synthetically produced acts like Simian Mobile Disco and Crookers led the way, because he himself seems to live in a world that is half real and half synthesized. Like mentor Kanye West's 808s & Heartbreak, Cudi has found a sweet spot between hip-hop and electronically enhanced singing, even if it was sometimes hard to tell if he was actually singing live along to the tracks.

If that wasn't your scene, the men of Bon Iver were sure to mellow you down easy with the droney strains of "Lump Sum" and "Blood Bank" and perhaps the strangest mass festival sing along ever, the plaintive "Skinny Love," with its refrain of "Now I'm breaking at the britches/ And at the end of all your lines."

The schizophrenia continued back across the way, as the funky hippie techo of STS9 mutated into the spastic gothy beats of Crystal Castles and then the psychedelic mindstorm that is Of Montreal. What other band's lead singer is carried on stage by a pair of Skeletor-looking monsters for a set of short-attention-span pixie-pop that included masked ninjas battling a gigantic female sumo wrestler, transvestites in one-legged leotards releasing balloons and pajama-wearing goons in gasmasks delivering Christmas presents filled with smokebombs?

In addition to playing such fan favorites as "Nonpareil of Favor," "For Our Elegant Caste" and a beat-assisted version of "Wraith Pinned To the Mist," the kaleidoscopic set also featured a surprise appearance by urban boho songstress and friend Janelle Monae for a cover of David Bowie's "Moonage Daydream."

The day's biggest crowd, however, belonged to Kings of Leon, who played the festival in 2007 and reminded the adoring crowd that their 2003 Lolla set was a disaster. After opening with the fiery three-punch combo of "Be Somebody," "Taper Jean Girl" and "My Party," singer Caleb Followil recalled how the then-new group played to just a handful of people back then, joking that when the meager crowds got a load of their mustaches and outfits, they quickly dispersed. That wasn't the case this time, though, as the now world-beating rock group funked up "Molly's Chambers" and "Crawl" with a grimy, Stonesy flair and created a chorus of tens of thousands on their breakthrough hit, "Sex on Fire."

It was hard to believe that jittery band Caleb spoke of was the same one whose soaring, radio-ready anthems were bouncing around the skyscraper canyons of downtown Chicago on Friday night, as if they belonged on the main stage all along.

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