I remember in an episode of I.M. Weasel, I.M. was tired of all the same old cartoon cliches and they had an episode where they did them all. I.M. discovered the reason for this was they were using old scripts. The first script was for an old Bugs Bunny cartoon, but then they crossed out Bugs's name and put Buster Bunny's name, then they crossed out Buster's name and put I.M. Weasel.