 A total of 29 people have subbed for David Letterman (qv) in  total. In 2000, as he underwent and recuperated from heart bypass  surgery: Charles Grodin (I) (qv), Regis Philbin (qv) (2 times),  Paul Shaffer (qv) (3 times), David Brenner (II) (qv) (2 times),  Tom Snyder (I) (qv) (2 times), Tom Arnold (I) (qv),  Bill Cosby (qv), Kathie Lee Gifford (qv), Nathan Lane (qv),  Janeane Garofalo (qv), and Dana Carvey (qv); in 2003, as he  recuperated from the shingles: Bruce Willis (I) ,  John McEnroe (qv), Regis Philbin (qv), Whoopi Goldberg (qv),  Vince Vaughn (qv), Elvis Costello (qv), Will Ferrell (qv),  Megan Mullally (qv), Brad Garrett (I) (qv),  Tom Dreesen (I) (qv), Bonnie Hunt (qv), Paul Shaffer (qv),  Bill Cosby (qv), and Luke Wilson (I) (qv). Guest hosts who  filled in for Letterman in June for no apparent reason ("Tired Ass  Syndrome"): Tom Arnold (I) (qv), Tom Green (III) (qv),  Kelsey Grammer (qv), and Jimmy Fallon (qv). In November 2003,  Paul Shaffer (qv) filled in for Dave because of his girlfriends  (Regina Lasko ) delivery of their baby, Harry Joseph. In 2005,  "Paul Shaffer" filled again as host, after Letterman went to accept  a car award in Detroit. In 2007, Adam Sandler (I) (qv) stepped in  after Letterman caught fever earlier in the day.