An item from Tony Williams on LinkedIn drew my attention to Chris Swain's comparison of the six chemical structure drawing packages used by ChemSpider: http://homepage.mac.com/swain/Sites/Macinchem/Reviews/chem_drawing_packages/.... Wendy Dr. Wendy A. Warr Wendy Warr & Associates 6 Berwick Court, Holmes Chapel Cheshire, CW4 7HZ, England Tel./Fax +44 (0)1477 533837 wendy@warr.com<mailto:wendy@warr.com> http://www.warr.com<http://www.warr.com/>