Thomasina's Guide To Geeky Knitting merges yarn with scientific subjects. This highly-specialized site includes samples dealing with geology, paleontology, genetics, microbiology, anatomy, ecology, topology, fractals, geometry, history and linguistics. Definitely one for brainy folks with lots of time and patience.
The Bioephemera website contains a hodge-podge of topical elements, but mostly focuses on the intersection of biology and art. This particular link is to the "skulls" section. A unique site for folks who enjoy living things looked upon as cultural relics.