"Hilarious" is an adjective that never belongs in the same sentence as the proper noun "Jay Leno." Except when Louie C.K. is his guest. The two comedians started exchanges barbs at each other, culminating in C.K. telling Leno, "You're the weirdest looking person on the planet earth." Leno managed to get a dig in about C.K.'s Dunkin Donut habit. Check it out.