GRAPEVINE

By DAVID ELLIS

The life cycle of a TV sensation can be stunningly quick: from talk-of-the- tube to zap-inducing bore in just a few weeks' time. A look at the trajectory of TV's meteoric names:

Bart Simpson The ultimate cautionary tale: from cameo appearances to T-shirt overexposure in just one year. Now cross-channel rival Bill Cosby is crowing that he survived the Bart challenge.

Wolf Blitzer The man with one emotion (stoicism) and a singular name launched a thousand late-night gags. Now that the war's over, his popularity may evaporate. But as a serious journalist, he's probably better off without the hubbub. Just ask Arthur Kent, the Scud Stud.

Homey the Clown The abusive character on In Living Color was a favorite with gulf soldiers, who yelled his phrase "Homey don't play that!" after hitting enemy targets. In New York City a 10-year-old bragged that he was imitating the ornery Homey when he hit an old lady on the head with a sock full of sand.

Nancy Weston After months of suspense, thirtysomething's writers let her triumph over cancer and bumped off goldilocks Gary instead. But if the show is renewed, viewers may question whether the oh-so-plucky Nancy was worth the trouble. Why did she marry such a jerk, anyway?

The Copy-Machine Guy Wondering why your co-workers keep using dumb variations of your name? Blame Saturday Night Live's latest character, Richard Layman, an annoying office nerd who sits near the copier and tries too hard to be everyone's friend. Who? You know, the Richmeister, Rich-ster, Rich-O . . .

With reporting by DANIEL S. LEVY