Madness is a port of a toy with the same name from RISC OS. When started, your windows move around your desktop in a semi-random fashion, bouncing off screen edges, the panel, etc. Some people like to leave it running while they work. Why they do that is for psychologists to answer.
For KDE 2: madness-1.2.tar.gz
For KDE 3: madness-1.2-kde3.tar.gz