26. Letterman on Affair
David Letterman spent 10 minutes on the air, detailing an extortion plot that threatened to expose his affair with a co-worker. This is incredible television. (Please don't take it down, YouTube!)
27. Madonna on David Letterman
On The Late Show with David Letterman, Madonna jokes about Alex Rodriguez, denied marriage rumors and ate pizza. Watch this hilarious clip.
28. David Letterman Apology to Sarah Palin
David Letterman apologizes a second time for his comments about Sarah Palin and her daughters. There's no defense of it, he says.
29. Letterman Reacts to 9/11
In a truly heartfelt few minutes of his talk show, David Letterman reacted to the events of 9/11. It was as moving as any on-air tribute can be and we only bring it up now to shove it in the face of Sarah Palin: with no history of controversy whatsoever, is this really a man you wanna imply is a pedophile? You should be ashamed of yourself, Governor.
30. David Letterman Disses Joan Rivers!
Take this, Joan Rivers! David Letterman jokingly walks out on the comedian in this clip.
Wait! There's more Unforgettable Moments in David Letterman History! Just click "Next" below: