A great collection of Fair Dice, Iamonds, Eternity, Mazes, Atom Stability, Dissections, Kites&Bricks, Triangles, Retrograde, Pentagons, Prize Problems, Books, Links, Chaos Tiles, and Partridges by Ed Pegg Jr.
Not all computer games are frenzied action or arcade romps! Launched in 1995 Quandary is committed to supporting players who prefer exercising their mind rather than their trigger finger.
Kevin Stone's unique collection of brain teasers, games and optical illusions. With over 1,200 teasers, 102 awards and around 1,400,000 Visitors per year, this site claims to be the world's most popular brain teaser resource.
The World Puzzle Federation is an international association of puzzlers and puzzlers' groups. It hosts the World Puzzle Championship, an annual event since 1992.
The Open Directory Project is the largest, most comprehensive human-edited directory of the Web. It is constructed and maintained by a vast, global community of volunteer editors.
Puzzle projects by Peter Grabarchuk, including puzzle products, books and publications, web puzzles and other puzzle activities.
From Tricky and Clever Puzzles through Baffling and Perplexing Illusions to Cognitive Toys.