The Necronomicon Project is an HTML collection of various texts, illustrations, and other pieces related to the (apparently) fictional tome created by H.P. Lovecraft as a reference device for his Cthulhu mythos. This beatifully-designed website does a masterful job of drawing together all of the intricate and fabulous works inspired by Lovecraft's stories.

http://www.chaosmatrix.org/library/books/necro_proj/