Flexagons	Cube-like Puzzles
Polyforms and dissection	Mazes
News and Mailinglists	Linklists
Companies and Catalogs

Museum of Puzzles	Puzzle Classes and definitions and a lot of beautifull pictures of puzzles
The Slocum Puzzle Foundation	The Slocum Puzzle Foundation was established on August 10, 1993 as a nonprofit public benefit Corporation. It was approved by the State of California and the U.S. Government as a charitable and educational Foundation. The purpose of the Foundation is to educate the public on puzzles, their history, development, and use in various cultures of the world. The Foundation will actively support the use of puzzles for education.
The Object Server Home Page (COS)	The idea is that you specify a type of combinatorial object, together with specific parameter values, and COS will return to you a list of all such objects. COS can generate permutations, combinations, various types of trees, unlabelled graphs, linear extensions of posets, pentomino puzzle solutions, numerical partitions, and a host of other combinatorial objects.
Puzzle People Page	Directory of Mechanical Puzzle Collectors. This page will hopefully eventually cover much of the information available in Jerry Slocum's Directory of Puzzle Collectors (subject of course to the permission of the collectors there). It's purpose is to help puzzle collectors find and write to other collectors with similar interests.
Hirofumi Fujiwara	Some good puzzle forms and java-versions! Nice site.
Chosi	His Puzzle Collecting Page. Includes his collection and some more information e.g on manufacturers.
Mathpuzzle.com	Some very interesting puzzles. Regularly updated. And has a maillinglist to keep you informed about updates.
rec.puzzels archive	A HTML-version of the rec.puzzles archive (at tudelft)
Other puzzles from rec.puzzles	at xraysgi.ims.uconn.edu. Collected by David Moews
Puzzle Index	at the Centre for Innovation in Mathematics Teaching. Some nice puzzles... some oldies but also some not so old..
The Geometry Junkyard	These pages contain usenet clippings, web pointers, lecture notes, research excerpts, papers, abstracts, programs, problems, and other stuff related to discrete and computational geometry. Some of it is quite serious, but I hope much of it is also entertaining. The main criteria for adding something here are that it be geometrical (obviously) and that it not fit into my other geometry page, Geometry in Action, which is more devoted to applications and less to pure math. I also have another page on non-geometrical recreational math.
The Pi Trivia Game	Do you think you a lot about Pi check this out ...
Cut-the-knot	Interactive Mathematics Miscellany and Puzzles
Lewis Carroll	Puzzles and Games from the famous author of Alice in Wonderland...
Unsolved Mathematics Problems	Some conjectures/puzzles and (partial) answers...
USAMTS puzzles	"All high school students in the United States are hereby cordially invited to take part in the USA Mathematical Talent Search (USAMTS). While most other competitions have stringent time limits, the USAMTS allows for more reflection on the part of the participants. We wish to foster not only insight, ingenuity, quick thinking, and creativity, but also writing skills and the virtue of perseverance. The USAMTS consists of four rounds, with each round featuring five problems." Problems worth puzzling...
Ken Duisenberg	's Puzzle of the Week. With archive. Some interesting puzzles
Geometry POTW	Math Forum - Problem of the Week
Puzzle Fun	PUZZLE FUN is a bulletin about polyominoes and other puzzles. In each number you have a differentis issued from 2 to 4 times a year. This is the "On-line" version. topic. It
Puzzle Images	A page by Tom Longtin with beautifull computer generated 'proto-type' puzzles
Scott Kim	Mostly links. Also an artt. on "Games for the Rest of Us".
Mathematical games	A page with some of the history of Mathematical games and recreations
Puzzle Ring Home Page	The Puzzle Ring is an ever-expanding ring of web pages devoted to puzzles, including crosswords, word searches, Java puzzles, cryptograms, word games, mazes, logic problems, and just about any other puzzles you can think of. Take a look at the list of all connected-sites to see if there are some interesting new ones. I find most of them are not interesting but you might...
A random puzzle site	each time a random puzzle-site of the puzzle ring.
The Prisoners' Dilemma	A short text about ... yes
IQ Test	not really puzzles but what it says.
The Puzzler	I do not like most presented puzzles here, but you might.
WGRweb	World Game Review. A magazine concentrating on areas not heavily coverd by other magazines.
thinks.com	1001 uses for a playful brain. Slightly dry. But still some things are interesing
Homepage of Torsten Sillke at Univ. Bielefeld

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