These are animations of the electronic energy levels of the hydrogen atom. They depict the probability that the hydrogen atom will be found in a certain point in space. This probability is drawn as a cloud colored with the rainbow colors, ranging from red (low probability) to blue-magenta(high probability). The levels are numbered according to their quantum numbers nml. I've just included some of the cooler-looking ones.
These animations are Copyright (c) Juan F. Herrera. Permission to reproduce them is granted provided proper credit are given to the author.
http://www.geocities.com/juanfh/tracker_cellar/