Faunmap. An electronic database documenting late Quaternary distributions of mammal species in the U.S.; it allows users to learn about & investigate the evolution of mammalian communities during the last 40,000 years.
History of Palaeozoic forests. English translation of a paper by Hans Kerp from Natur und Museum 126(12): 421-430. Good introduction to Carboniferous paleobotany.
Paleontology Without Walls. An online exhibit of phylogeny, geology and evolution, along with links to resources on the Web .
Polyglot Paleontologist. English translations of non-English paleontological literature (mostly vertebrate).
Strange Science: The Rocky Road to Modern Paleontology and Biology. A very entertaining site chronicling some of the less distinguished moments in the history of paleontology. Excellent section on biographical data for early paleontologists.
UC Berkeley Museum of Paleontology. Take a tour of a nifty museum; it's more than just fossils!