ChemSpider
http://www.chemspider.com/

ChemSpider makes available a database of chemical structures and related properties as well as providing access to a series of property prediction algorithms. It has been built with the intention of aggregating and indexing chemical structures and their associated information into a single searchable repository and making it available to everybody, at no charge. ChemSpider intends to become a community for chemists to share data and knowledge associated with chemical structures and reactions and providing an open forum for discussion and sharing. Over 10 Million ( 10,671,437 ) Compounds Indexed and Growing… This has been added to the tools section of Research Resources Subject Tracer™ Information Blog. This has been added to Biological Informatics Subject Tracer™ Information Blog.