Troubled singer Amy Winehouse

Troubled singer Amy Winehouse - who checked out of a London rehab clinic last month - has a new party trick: snorting vodka.

Winehouse shocked onlookers when she nasally inhaled the potent spirit through a straw while partying with friends including Kelly Osbourne, Mark Ronson and Kimberly Stewart at London's Bungalow 8 club on Wednesday.

A source said: "Somebody had brought over 20 shots to Amy's table and she decided to show off her new party trick.

"She necked the top of the shot and lit the rest with a lighter. Then she grabbed a straw and sucked what was left up her nose.

"Amy threw back her head and reeled in shock and everyone around her looked stunned."

Doctors have warned Amy's party trick, known as a Gas Chamber, could be potentially lethal as alcohol is absorbed directly into the bloodstream.

Meanwhile, the 24-year-old Rehab star flew into a rage Thursday when she spotted an unauthorised biography about her on sale at her local London garage.

Amy - who popped into the shop to pick up some sweets on her way home after partying till 5am - demanded the £17 tome, titled Amy, Amy, Amy: The Amy Winehouse Story, be taken off the shelves immediately.

The book, by Nick Johnstone, details Amy's rise to fame her battle with drink and drugs and the arrest of her husband Blake Fielder Civil, who is currently awaiting trial at London's Pentonville Prison.