"Where you guys sleeping? In a field?" a curious Thom Yorke asked the Radiohead  faithful during the band's headlining set at Bonnaroo on Friday night (June 8). "Do you do that here? I dunno." It was almost like Yorke and co. had never visited the sprawling music fest in before, but of course, the alt-rock giants delivered an epic performance in Manchester six years ago, when Bonnaroo was still growing into the amalgamated mega-fest it is today. As the first of the three major headliners at this year's event, Radiohead was given another opportunity to make a field of thousands weep along with the most beautiful falsetto in rock music.
LIVE AT BONNAROO -- FRIDAY HIGHLIGHTS
Radiohead's two-hour, two-encore headlining set focused primarily on the band's two most recent albums (2007's "In Rainbows" and last year's "The King of Limbs"), but re-shaped classics like "Everything In Its Right Place" and "Karma Police" made the performance the easy, expected highlight of the day. But hours before and after Radiohead, festival goers were partying hard to the muscular dance-rock of Little Dragon , austere jams of Afrocubism , darling soul music of Michael Kiwanuka and earthquake-like bass of Major Lazer . Meanwhile, the temperature rose, food vendor lines lengthened, marijuana deals were made in daylight, breasts were exposed, and everyone seemed to have a roaring good time.
What was going on behind the scenes and way out in the open at Bonnaroo on Friday? Here are 10 things you might have missed:
1. The following words were uttered to the crowd by Thom Yorke before playing new song "Supercollider": "This song is for Jack White . We saw him yesterday. A big thank-you to him, but we can't tell you why. You'll find out." What does this mean? Click here  for some hardcore speculation.
• Thursday Highlights 
2. "This is my first Bonnaroo, y'all gotta make more noise than that!" Ludacris  told the crowd -- by any calculation, one of the high-decibel groups of the day -- in This Tent after opening his set with "Number One Spot." As the Atlanta rapper ran through his cavalcade of hits, Donald Glover, AKA Childish Gambino , watched from the wings and nodded along dutifully, although he did not make a special appearance next to Luda.
3. Two of the night's biggest acts gave subtle shout-outs to the recently deceased Beastie Boy Adam "MCA" Yauch  : Radiohead's Thom Yorke rolled out a keyboard with the Tibetan flag draped across its back, a reference to Yauch's Tibetan activism that Yorke has made in recent concerts. Less than an hour later, in between tracks like Tyga's "Rack City" and their own "Pon De Floor," Major Lazer dropped the Beasties' "Intergalactic" in MCA's honor.
4. Foster The People  were slotted with a 75-minute set and made the most of it, relying on a unique stage setup and saving their smash "Pumped Up Kicks" for the tail end of their performance. However, the band also inspired the snarkiest line of the night, courtesy of a photographer waiting in line to be ushered back to shoot Radiohead's performance: "Foster The People? Eh. I liked them better when they were Peter Bjorn & John." That, my friends, is how you diss a rock band like a hipster.
5. In the Battle of the Early Day Covers, the Soul Rebels  ' take on Stevie Wonder 's "I Wish" was narrowly beaten out by BBC Sound of 2012 winner Michael Kiwanuka's soaring version of Jimi Hendrix 's "May This Be Love." One day earlier, the Dirty Guv'nahs trotted out a Southern-fried cover of "Hey Jude" that played out rather... dubiously.
6 As the Comedy Tent drew huge swaths of the crowd, comics mingled amongst the musicians in the press and artist areas: Rhys Darby, best known as "Flight of the Conchord's" Murray, sported a Def Leppard  tee and camo pants as he hit the press junket, while "Curb Your Enthusiasm's" J.B. Smoove and "Key and Peele's" Jordan Peele congratulated each other on their recent successes at the bar in the artist area close to 1 AM.
7. Christopher Mintz-Plasse, aka "McLovin'" from "Superbad," was spotted in the VIP area for Little Dragon, sporting a tank top with slicked-up hair an in-the-process mustache. He jammed out next to the press and VIP guests before being escorted back to an even more exclusive viewing spot by the band's publicist.
8. Radiohead's Jonny Greenwood came oh-so-close to getting through the band's set unscathed, but the guitarist sliced his right hand open while ripping through "Bodysnatchers" during the first encore. Fortunately for the crowd, Greenwood soldiered on, and even helped out on the night-closing "Paranoid Android."
9. "More help!" the Avett Brothers  repeatedly summoned to the audience during their main stage set's climactic song, "I And Love And You." After multiple calls for vocal assistance, the song became the most spirited -- even emotional, perhaps -- sing-along of the day, reminiscent of Mumford & Sons' "Little Lion Man" at last year's fest.
10. Bonnaroo 2012 will forever be remembered as the festival in which everyone in earshot talked about bath salts. With the recent waves of nightmarish news stories in which bath salts had been used as a narcotic, 'Roo attendees were constantly overheard joking about taking bath salts or simply yelling the phrase "bath salts." Fortunately, no one seems to have taken the stuff -- or else I'd be wearing a goalie mask right now.
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