Wikipedia
XPenguins is an X Window System screenmate program that shows an animation of various penguins involved in various activities, such as reading, falling, digging, skating, etc. The program moves the penguins around as if the windows were solid objects the penguins could stay, walk, or skate on. The program has been written and is currently maintained by Robin Hogan. The penguin images are mostly taken from the Pingus game.
The program is configurable to use an arbitrary theme—a set of images to be used in place of the standard penguin cartoons. For example, one theme included in the standard XPenguins distribution is based on drawings supposedly depicting Bill Gates.
Ubuntu Software Center includes listings to install both version 2.2 of xpenguins and version 2.1.1 specifically for Gnome Panel.
A Microsoft Windows version of the program, called WinPenguins, has been developed by Michael Vines.
A JavaScript port, called JSPenguins, has been developed by Peter G Smith.