Gary Busey is no stranger to weird public antics (remember: he will tear out your endocrine system!), but this red-carpet appearance at the 2008 Oscars is the jewel in his madman's crown. When Busey interrupts Ryan Seacrest's interview with Laura Linney and Jennifer Garner — and plants a wet one on the petrified Garner's vulnerable neck — the ladies do what pretty girls in bars have been done for decades: smile sweetly at the crazy man and back away for some "girl talk." Busey's later apology was almost as incomprehensible as his original transgression. — Lindsay Armstrong

In 1986, Sam Phillips — the founder of Sun Records and producer for such rock legends as Elvis Presley, Johnny Cash and Roy Orbison — forged his own legend when he showed up on Letterman high as a kite. Phillips had just been inducted into the Rock and Roll Hall of Fame; it's logical that he wanted to celebrate, but everything that transpired next completely defied logic. Here, Phillips set the template for the Joaquin Phoenix interview — looking and behaving like a Montana militiaman is the surest way to Dave's heart. — Cyriaque Lamar

Nobody expected Mike Tyson to be Proust in this live interview, but then again nobody — least of all New York sportscaster Russ Salzberg — expected sixty-four seconds of expletives, threats, and a terrifyingly awesome demand to "turn off your station." In this clip from January 1999, Salzberg attempts to speak with Tyson about his comeback match with Francois Botha. After his famously ill-fated fight with Evander Holyfield, Kid Dynamite apparently had a chip on his shoulder (or some earlobe between his molars). — C.L.

"I'm getting dizzy." This confession should be unusual at the beginning of an interview, but it is, after all, Richard Simmons. The man's history with David Letterman is a storied one, so it's hard to pick just one Late Night appearance for this list. The episode where Letterman doused Simmons with a fire extinguisher might seem like the frontrunner, but Richard's insistence that his vegetable steamer has a brain puts this one over the top. While Dick and Dave quibble over the price of the thing, it goes off like a bomb, and sends Simmons screaming across the room, patting his hair to make sure it's still on his head. Immortal. — Marian Lorraine

Norm MacDonald was on top of the world — or at least the Weekend Update anchor desk — when he visited Conan in 1997. Though Conan prefaces the interview by saying Norm's been quite ill, we're not sure his incoherent ramblings can be blamed solely on bacteria. MacDonald reveals his scintillating creative mind, his slurred, incoherent rambling showing exactly why SNL in the '90s just got, um, better and better. He repeatedly references "ass fluids" and insults the disabled (combining both when discussing Larry Flynt!), then attempts to spread his love/germs on fellow guest Courtney Thorne-Smith. Conan sums up the interview by calling Norm "the biggest ass I've ever met." — L.A.