He's known in this country mainly for "Loser", last year's maddeningly catchy hit which laid nonsensical lyrics over an unforgettable twanging guitar loop and shuffling beatbox rhythms. But Beck isn't interested in duplication. In fact, he did everything in his power to sabotage the crowd's karaoke version of "Loser", turning its refrain of "I'm a loser, baby/ So why don't you kill me?" into "Dur-dur-de-dur-dur", which made about as much sense as the rest of the song. In Beck's hands, the rules - like sticking to the right lyrics, arrangements and even instruments - become deliciously fluid. Beck himself looked surprised when a burst of sampled mooing erupted. "Uh...'Bovine Blues' ", he offered. Give this man a technical hiccup and he'll give it a title.
Many of the songs are unprintable (though if you own the album, you won' t be surprised that track 3, side 1 was a funky opener). All of them are unpredictable, like the closing one, which had Beck strapping on a keyboard and picking out a cheesy Rockford Files-type tune, ending under an avalanche of feedback. Then he told us that we had been "a great pile of people". And him? The very worst you can say is that the Elvis jumps could use some work.
Smashing Pumpkins headlined the first day, disposing of their best-known songs within the first 15 minutes. That left room for an entire set of virgin material from their forthcoming double album. Our joy was unbridled. Singer Billy Corgan had "I Love My Mom" felt-tipped on his guitar, but don't expect a collaboration with the St Winifred's School Choir just yet - the new songs are as tough as your grandmother's feet, and about as exciting.
The Pumpkins were upstaged by Hole's appearance earlier that evening, which climaxed with Courtney Love shoving amps and monitors into the pit. The drum-kit wasn't such a pushover. It did what no man, woman or journalist has yet attempted: it fought back. As Love flailed beneath a blaze of snares and high-hats, you found yourself cheering the rhythm section for the first time.
Her petulance couldn't overshadow two moments which brought tears to her eyes and ours: a bruised-purple "Doll Parts" and a skeletal reading of Nirvana's "Pennyroyal Tea", scratched out on two crackling electric guitars. As it accompanied a Reading dusk for the second time (the similarly tragic Manic Street Preachers tore through it here last year), you prayed that Love would confound expectations by surviving, and making more albums as shattering as Live Through This, and intimidating all but the bravest drum-kits.
Saturday delivered nothing like the same excitement. The blistering Little Axe needed the claustrophobia of a club setting to dazzle. Tricky needed to put his mind on his work. And Shed Seven just needed shooting.
It was left to Bjork to give us a reason for living. She bounced about like a kangaroo, shriek-singing in non sequiturs: everything that your average two-year-old spends her life doing. Her capacity for reinvention has a childish logic, too. Like Beck, she burrowed through her back catalogue like a child in her mother's wardrobe, becoming something that was at once gaudy and preposterous and magical.
So the disco throb of "Big Time Sensuality" was put in a hot wash and came out tiny and distant. That felt wrong, while "Venus as a Boy", reduced to just Bjork and a trilling harpsichord, achieved a incandescence that erased the original from memory. Nothing could have topped the batty cabaret finale of "It's Oh So Quiet" except ear-splitting fireworks carving patterns in the night sky. Which was just what we got, funnily enough. By the end of it, everyone was dancing, despite the fact that the music had stopped.