Letterman is the king. I've never thought Leno was fun...ever. Conan has his moments, but he can't adlib unconmfortable humor between the gags like Letterman can.
Leno, Conan, Letterman...all of them pale next to Craig Ferguson. http://www.youtube.com/watch?v=Q2E2hQp-094 http://www.youtube.com/watch?v=TyuDAzzKnz8 http://www.youtube.com/watch?v=uiE17ADgLsg -hl718
His voice is the only thing about him that's funny I went to IMDB here are all the Episodes of the simpsons Conan has his stamp on Stark Raving Dad (19 September 1991) - producer Mr. Lisa Goes to Washington (26 September 1991) - producer When Flanders Failed (3 October 1991) - producer Bart the Murderer (10 October 1991) - producer Homer Defined (17 October 1991) - producer Like Father, Like Clown (24 October 1991) - producer Treehouse of Horror II (31 October 1991) - producer Lisa's Pony (7 November 1991) - producer Saturdays of Thunder (14 November 1991) - producer Flaming Moe's (21 November 1991) - producer Burns Verkaufen der Kraftwerk (5 December 1991) - producer I Married Marge (26 December 1991) - producer Radio Bart (9 January 1992) - producer Lisa the Greek (23 January 1992) - producer Homer Alone (6 February 1992) - producer Bart the Lover (13 February 1992) - producer Homer at the Bat (20 February 1992) - producer Separate Vocations (27 February 1992) - producer Dog of Death (12 March 1992) - producer Colonel Homer (26 March 1992) - producer Black Widower (9 April 1992) - producer The Otto Show (23 April 1992) - producer Bart's Friend Falls in Love (7 May 1992) - producer Brother, Can You Spare Two Dimes? (27 August 1992) - producer Kamp Krusty (24 September 1992) - producer A Streetcar Named Marge (1 October 1992) - producer Homer the Heretic (8 October 1992) - producer Lisa the Beauty Queen (15 October 1992) - producer Treehouse of Horror III (29 October 1992) - producer (as Creepy Conan O'Brien) Itchy & Scratchy: The Movie (3 November 1992) - producer Marge Gets a Job (5 November 1992) - producer New Kid on the Block (12 November 1992) - Writer (written by), producer Mr. Plow (19 November 1992) - producer Lisa's First Word (3 December 1992) - producer Homer's Triple Bypass (17 December 1992) - producer Marge vs. the Monorail (14 January 1993) - Writer (written by), producer, Soundtrack (writer: "The Monorail Song") Selma's Choice (21 January 1993) - producer Brother from the Same Planet (4 February 1993) - producer I Love Lisa (11 February 1993) - producer Duffless (18 February 1993) - producer Last Exit to Springfield (11 March 1993) - producer So It's Come to This: A Simpsons Clip Show (1 April 1993) - producer The Front (15 April 1993) - producer Whacking Day (29 April 1993) - producer Marge in Chains (6 May 1993) - producer Krusty Gets Kancelled (13 May 1993) - producer Homer's Barbershop Quartet (30 September 1993) - producer, supervising producer Cape Feare (7 October 1993) - producer, supervising producer Homer Goes to College (14 October 1993) - Writer (writer), supervising producer Rosebud (21 October 1993) - supervising producer Treehouse of Horror IV (28 October 1993) - Writer (writer) (as Watch Conan O'Brien), supervising producer (as Conan ''12: 30 NBC'' O'Brien) Marge on the Lam (4 November 1993) - supervising producer Bart Gets Famous (3 February 1994) - Himself (voice)