Crrently quite sketchy here, caveat emptor!
Pun intended, you can find chemsketch here! - Brief course in chemistry, "what is a compound" to quantization of energies. An outline only as it is quite sketchy. Front page has three showcase java applets for exploring chemistry - the periodic table, reactions on a copper penny, molecules in 3d. Well organised links to other chemistry resources.

Periodic tables these resources were harvested from Richard Byrnes excellent blog: periodic table in videos The periodic table of comic Books comic book resource for each element The “Dynamic periodic table” a table with pop up links to further information The aufbau principle nicely explained

Video's/On line courses The Chemistry section from the MIT highlights for High schools section of the open course ware resources.

Free programs for computational chemistry:

The latter you'll need to compile in the cygwin environment.

A list of instructables
Gas Volume molecular model A chemical search engine This is a specialist search engine designed to expand your search to equivalent formats i.e. CAS number etc, and the go get results. (Comercial), the following info is provided by the supplier of the link: Digital Content for upper primary to leaving cert higher level. Excellent animations and videos covering all areas of the curriculum clarifying some difficult concepts. Variety of subscription options.