Our dog Grace (an American Eskimo) loves to rehearse for the part of "White Fang". She will stare into the mirror or even sit on our lap and growl and snarl and bare her teeth, until you stop looking at her, then she'll paw at us and whine to get our attention again and go right on rehearsing.
Another game we made up is...kill Flipper. She hates the sound Flipper makes on TV, so I make a funny sqeeking noise and we run all over the house trying to find Flipper--looking under the counch, in the closet, around corners, etc.