When microbiologists aren't curing diseases, they create works of art in petri dishes. In fact, they have an annual competition at the international Genetically Engineered Machine (iGEM) conference. This entry, inspired by Super Mario Bros., was submitted by the nanobiology laboratory at the University of Osaka. You can view a gallery of petri dish art at the link.
via Popular Science
UPDATE 12.20.09: Apparently we're having virus problems, so I deleted the link. I would not have guessed that New Scientist would be a bad risk.
Chock full o'virus for the holidays...