Chemistry 

ChemCenter: A Service of the American Chemical Society
Links to Web resources developed by the ACS Publications Division and the Chemical Abstracts Service as well as to Internet sites of scientific associations, publishers, vendors of information services, universities, and other content providers.

The Chemical Industry Home Page
Major headings include chemical industry associations, management resources (including stock prices), chemical and process engineering resources, chemical sales resources, environmental resources, analytical chemistry resources, and chemical company websites.

CHEMINFO: Chemical Information Courcen from Indiana University
CHEMINFO Chemical Information Sources, is designed to help people find and learn how to use chemical information resources on the Internet and elsewhere. It brings together Web sites at Indiana University with significant chemical information content.

Analytical Chemistry Information on the Internet
Presents an index listing of analytical chemistry resources on the Internet.

Chemistry Software
Software to cover Chemical, Mechanical, Electrical, and Instrumentation Engineering  disciplines, as well as providing selected software in the fields of Cost Estimating, Risk   Analysis, CAD (Plant design), and Statistical Process Control.  Software products available cover all aspects of engineering design in chemical and gas processing, power generation,  and oil refining industries. Specific software categories include process    flowsheet simulation, pipe stress analysis, pressure vessel and heat exchanger design, hydraulic flow calculations, finite element analysis, plant cost estimation, and chemical properties  estimation.

Chmoogle
An open-access chemistry search engine that aims to provide all publicly available chemical information for free. This site offers numerous features that can be extremely valuable.

Nist Chemistry Web Book
Provides thermochemical, thermophysical, and ion energetics data compiled by NIST under  the Standard Reference Data Program.  National Institute of Standards and Technology's  most recent release of NIST Standard Reference Database Number 69.

Web Elements  
An interactive periodic table of elements.  The author is Mark Winter, Department of Chemistry, University of  Sheffield, England.  WebElements aims to be a high quality source of chemistry information on the relating to the periodic table.