Jay Leno checked himself into a hospital in Burbank after canceling Thursday's show last minute. No word on what ails Leno, but an NBC rep says he's doing fine: "He was kidding around with the hospital staff and running his monologue jokes by the doctors and the nurses." Leno, who is famous for his work ethic and never calls in sick, also cancelled his Friday show. Ryan Reynolds—and an animal handler and small menagerie of reptiles—were expected to appear on Thursday's show. It was the first time Leno canceled a taping since he took over the show in 1992.