Chemistry Data Bases

Periodic Table
Theodore W. Gray’s Periodic Table
SDBS (Spectral Database for Organic Compounds)
PhotochemCAD (optical data via Oregon Medical Laser)
pKa Table
Name Reactions
IUPAC Nomenclature

Chemistry Resource Collections

ChemSpider (search and share chemistry by RSC)
Not Voodoo
Organic Chemistry Resources (U Wisconsin)

Chemistry Programs

UCSF Chimera (visualization and analysis of molecular structures)
Cambridge Crystal Strucure Data Base (for Mercury CSD Crystal Structure Visualisation)
Isotope Distribution Calculator and Mass Spec Plotter (one of many)

Publishers

ACS Journals
RSC Journals Finder
Wiley Online Library Chemistry
Springer Journals Chemistry
ScienceDirect (Elsevier)
Science
Nature
Nature Chemistry