David Caldwell's Realm
I've also been spending a lot of time writing solitaire games. Here's some links to games you can play right in your browser (or on your phone): Freecell Solitaire, Klondike Solitaire, Flower Garden Solitaire, Spider Solitaire, Sea Haven Towers Solitaire.
"The fundamental principle of science, the definition almost, is this: the sole test of the validity of any idea is experiment." -- Richard P. Feynman
If you feel so inclined, you may browse my CD collection...