On last night's show, David Letterman wished his arch-nemesis Jay Leno a happy (?) birthday. From The Hollywood Reporter:

“Happy Birthday to Jay Leno. 61 years old today,” he said on his late night CBS show. “Jay, of course, being one of the few tyrants still alive. All of his friends got together and had a cake. Jay cut the cake with the same knife he stuck in Conan’s back.”

OWWW!!!!

ALSO? This.