"Knuckle-to-knuckle is big with athletes, replacing the dated high-five as a greeting or congratulatory gesture. Tiger Woods used to knuckle-bump his old caddy Fluff Cowan after a great shot, before he dismissed him. Many baseball players have substituted the knuckle for shaking hands with the other team, perhaps as a defensive move, speculated Kenny Mayne, ESPN's ''SportsCenter'' anchor. ''You keep your fist closed, and you're not going to get your hand hurt or lose any digits,'' he said."
"When Mr. Obama and his wife triumphantly took the stage in St. Paul Tuesday to claim the Democratic presidential nomination, the candidate, dressed in one of the crisp, neutral suits that have made him a GQ darling, was momentarily upstaged by his wife, and not just because she knuckle-bumped him in front of the world."