Cher, Madonna, Robin Williams, and others always give memorable interviews on ''Arsenio Hall,'' ''Late Night with David Letterman,'' and ''The Tonight Show''

You’re lying in bed, the remote control in hand, searching the airwaves for after-hours amusement. Should you tune in to Johnny, flip to Arsenio, or hold out for Dave? Always a painful choice, but ENTERTAINMENT WEEKLY can help. We stayed up late for weeks, downed gallons of coffee, and listened to hundreds of hours of celebrity chatter — all to bring you our picks for the top 10 talk show guests on the ’round-midnight circuit. For inside expertise, we consulted Robert Morton, producer of Late Night With David Letterman. ”Look for guests who understand the talk show format,” he said. ”The best guests understand that they’re expected to entertain, not just sit down and answer questions. And avoid those guests who come on just to plug a book or a movie — they’re the most boring.” The results of our star search, complete with a rating of one to five TVs, are compiled in this handy chart. When these folks sit down for a schmooze, it’s no time to snooze.

SOFA STYLE Always Outrageous
MEMORABLE APPEARANCE Late Night With David Letterman, Nov. 13, 1987
BEST BANTER ON THAT SHOW Letterman: ”You have tattoos all over the back part of your body…what is that exactly? It’s like a Rorschach thing there.” Cher, under her breath a few minutes later: ”A—- .”
Cher’s Frederick’s of Hollywood-style outfit: thigh-high boots, G-String, and black leather jacket

Martin Short
SOFA STYLE Irresitibly huggable
MEMORABLE APPEARANCE Late Night With David Letterman, Dec. 3, 1984
BEST BANTER ON THAT SHOW Short, recalling his early work with Danny Thomas: ”Dan is great…He gets on the phone and talks and talks and talks and talks. We’re still close.” Letterman: ”When was the last time you talked to him on the phone?” Short: ”Uh, 1981.”
BEST SIGHT GAG Short performs a dribble-take, a variation on that comedy classic the spit-take. Afterward, Letterman dumps two cups of water into Short’s lap.

Sandra Bernhard
SOFA STYLE Rivetingly obnoxious
MEMORABLE APPEARANCE The Arsenio Hall Show, Feb. 4, 1991
BEST BANTER ON THAT SHOW ”All of our consciousnesses are drawn to the crisis in the Persian Gulf,” a deadpan Bernhard says before launching into a tone-deaf version of ”The Cruel War.” An archly ironic joke or serious political statement? With Bernhard, you never know.
BEST SIGHT GAG Bernhard bares her feet in front of 4 million viewers

Penn & Teller
SOFA STYLE Savagely sarcastic
MEMORABLE APPEARANCE Late Night With David Letterman, Oct. 4, 1988
BEST BANTER ON SHOW Penn, apparently mad: ”Didn’t you have a guest on a few weeks ago you want to tell us about? Sigmund and Leroy? We thought we were your favorite male magic duo. And there…you got those foreigners out there with those stupid little animals.”
BEST SIGHT GAG Teller slices his palm open with a razor blade and then bleed profusely over Letterman’s desk. Later, Teller slits Penn’s throat with a butcher knife.

SOFA STYLE Wickedly flirtatious
MEMORABLE APPEARANCE The Arsenio Hall Show, May 1, 1990
BEST BANTER ON SHOW Madonna, teasing Hall about his relationship with Eddie Murphy: ”There is a rumor, and I want to know about it.” Hall’s response: ”Well, there’s a rumor about you and Sandra Bernhard — but I didn’t ask you about it.”
BEST SIGHT GAG Madonna’s Little Orphan Annie, finger-in-a-light-socket hairdo.

Robin Williams
SOFA STYLE Hilariously Manic
MEMORABLE APPEARANCE The Tonight Show, Jan. 10, 1991
BEST BANTER ON THAT SHOW On his first marriage: ”Divorce — from the Latin divartarum, meaning having your genitals torn out through your wallet.” On accidentally breaking Robert DeNiro’s nose on the set of Awakenings: ”All of a sudden it was Raging Mork.”
BEST SIGHT GAG Williams impersonates Sylvestor Stallone playing Hamlet: ”To be or what?”
TV METER *****

Shirley MacLaine
SOFA STYLE Emphatically flaky
MEMORABLE APPEARANCE Late Night With David Letterman, Oct.4, 1988
BEST BANTER ON THE SHOW MacLaine, after Letterman badgers her to describe her past lives: ”Maybe Cher was right — maybe you are an a—–.” Later, Letterman says of his own past-life experiences: “I vaguely have a feeling that…I delivered a pizza to the Eisenhowers.”
BEST SIGHT GAG MacLaine tugs Letterman’s hair to make sure ”it’s real.” (”Can I check for some things on you know, Shirley?” Letterman asks.)

Tony Randall
SOFA STYLE Exactly like Felix Unger
MEMORABLE APPEARANCE The Tonight Show, Aug. 24, 1990
BEST BANTER On a recent shopping trip: ”I went into this store and the manager said, ‘Oh, God! Tony Randall! Wait! I got to call my wife!” He flattered me so much I bought a ties and six shirts. I said, ‘Will you accept my check?’ He said, ‘Do you have identification?”’
BEST SIGHT GAG Too fussy for sight gags.

Teri Garr
SOFA STYLE Dynamically ditzy
MEMORABLE APPEARANCE Late Night With David Letterman, Nov. 20, 1985
BEST BANTER ON THAT SHOW Letterman repeatedly asks Garr to take an on-camera shower. ”I’ve gone past taking showers on television,” she responds. ”I’m not going to do it. My final answer on this is no.”
BEST SIGHT GAG Garr takes an on-camera shower during the closing credits
TV METER *****

Jonathan Winters
SOFA STYLE Part Twilight Zone, part Evening at the Improv
MEMORABLE APPEARANCE Late Night With David Letterman, April 24, 1986
BEST BANTER ON THAT SHOW On his hobby: ”I started out to be an artist. I still love to paint…I paint kind of surrealistic things, which means people lean in and go, ‘What is that? Why is the kitty wearing a watch on his face?”’
BEST SIGHT GAG Winters is a sight gag.