US rock show Bonnaroo has become the world's top-grossing festival after selling out in record time. The three-day event, which takes place in Tennessee this weekend (16-18JUN06), failed to sell out in 2005 and promoters feared fans would be slow to pick up tickets this year (06). But with headliners Radiohead and Tom Petty + THE HEARTBREAKERS signed up, fans are keen to get tickets for the fifth annual show. And the sell-out has made Bonnaroo the world's most successful festival. In 2004, Bonnaroo sold out and grossed $14.5 million (GBP8 million). Over 100 acts will perform on the festival's nine stages this weekend.