Currently these are in no particular order:

The Escher Sketch program
IUCr's Crystallography pamphlets
An alphabetical list of crystallographic software
Everything you wanted to know about CIF files
A set of tables of Atomic Radii from Nat Alcock (U. Warwick, UK), courtesy of Indiana University's Molecular Structure Center
WebElements Periodic Table.
Download Chime here. This will help look at all the pretty pdb files on your browser.
RasMol
WinGX
PLATON
POV-Ray a very cool Ray-tracing program that works with PLATON.

Can't find it on this page? Try here.

An amusing bunny which has nothing to do with crystallography.