http://www.erowid.org/
The Vaults of Erowid, is an online library of information about psychoactive plants and chemicals. It provides information about legal and illegal substances, including their desired and adverse effects. The site is organized by substance, ranging from common substances like alcohol, to unusual ones such as Bromo-DragonFLY.
The information on the site is a compilation of the experiences submitted by the site's users. Erowid acts as a publisher of new information as well as a library for the collection of documents and images published elsewhere.