Watch Howard Stern And David Letterman Trash Jay Leno

Late-night wars come and go, but grudges last forever. Renowned Jay Leno-hater Howard Stern joined David Letterman on tonight's "Late Show" to congratulate Letterman on his 30 years in late-night TV. And since Letterman hates Leno just as much as Stern does, what better way to celebrate than by spending five minutes talking smack about him!