They held the world's biggest celebration of leather, bondage and sexual fetish in San Francisco on Sunday, and due to the event's interactive nature, many people are now walking gingerly. "Enough is enough," said Lowell Clark, pulling up his blue jeans after emerging from one of dozens of spanking booths at the 25th Folsom Street Fair. Clark, a 30-year-old San Francisco waiter, conceded he was a novice at the booths, where men and women in search of stimulation were struck with whips, paddles or bare hands. Clark was last spanked at the age of 6 at the hands of his...