Charles Grodin, David Arquette, Willie Nelson, Lyle Lovett, and Kris Kristofferson Late Show with David Letterman : Season 6 Episode 129

The secret word is ""flange""; Dave holds up a certificate that makes Late Show the ""Official Late Night Talk Show of the Millennium""; Biff annoys Yankees players during his 2nd annual trip to their Spring Training camp in Florida; Lyle Lovett and Willie Nelson, with a little help from Kris Kristofferson, perform a memorable duet.