Interesting links

Hundreds of constants, data, information on chemicals:

http://webbook.nist.gov/chemistry/

the Chemistry Education Resource Guide;  quote: "chemistry study resources and chemistry teaching resources, as well as links to great blogs, journals, podcasts and a whole lot more":

http://www.smartscholar.com/chemistry-education-guide/

Drawing of chemicals and chemical formats in software:

http://openbabel.org

http://openbabel.org/wiki/Get_Open_Babel

To download the OpenBabel Installer directly, choose the link below: 

A free database for chemicals, here you can find the smiles notation for thousands of chemicals:

http://chemspider.com

Detailed information on Microsoft Excel:

http://spreadsheetpage.com/