I always liked this one where Johnny tracks down Don Rickles on the CPO Sharkey set to confront him about a broken cigarette box the previous night when Rickles was guest hosting.
Don Rickles on the Tonight Show
http://www.youtube.com/watch?v=fyxjEuFfxV0
I remember that. What a hoot. Rickles looked like a young kid called on the carpet by his father after a night of partying.