Brain Pictures - A set slices from an NMR brain scan, displayed using Javascript so that the user can view them in series by moving the mouse pointer. Non-scientific.
Comparative Mammalian Brain Collections - University of Wisconsin site has images showing the brain's internal architecture of specimens from over 100 mammalian species for studying differences in brain function and evolution.
Flybrain - An online atlas and database of the Drosophila nervous system.
GENSAT Mouse Brain Atlas at Rockefeller University - GENSAT is a collection of pictorial gene expression maps of the brain and spinal cord of EGFP BAC transgenic mice. These transgenic mice are available to the scientific community.
