I have seen cats that were entranced with chasing the mouse on an iPad game that is specially designed just for cats, but this is a new twist on the idea, and I think it is pretty awesome.
Cats will watch the little mouse running around on the iPad screen, and pretty soon, they will try to bat it and catch the mouse. When the cat's paw touches the screen of the iPad, it creates a blotch of colored "paint".
The cat continues to try and catch the mouse, each time leaving a new splotch of a different color on the painting. As long as the cat keeps on playing with the mouse, more and more places on the screen will be colored, until finally, you can have your very own painting made by your kitty-cat.