Xpenguins is a program for animating cute cartoons/animals in your root window. By default it will be penguins - they fall from the top of the screen, walk along the top of windows, up the side of windows and do various other stuff. Other themes in the base package are "Classic Penguins", reproducing XPenguins version 1.2, and "Turtles". More themes can be downloaded from the XPenguins web site.