Critical Math
   Articles and images on recreational math from fractals and magic squares to mathemorchids and Galois.
   http://web.onetel.com/~amygdala/articles/scimaths/

CuriousMath
   Include news, math tricks, methods, facts, trivia, mostly posted by users.
   http://www.curiousmath.com/

David Singmaster: List of Available Material
   Teaching and recreational items in this personal collection.
   http://anduin.eldar.org/~problemi/singmast/material.html

Eureka
   The annual journal of the Archimedeans, the mathematical society of the University of Cambridge. It regularly contains articles on recreational mathematics.
   http://www.archim.org.uk/eureka/

Fair Dice
   Contains a complete list of all possible Fair Dice, most of which are not cubes. Includes pictures.
   http://www.mathpuzzle.com/Fairdice.htm

Fast Arithmetic Tips
   Three categories: defensive - know to check an answer, offensive - fast mental calculations, and math magic.
   http://www.cut-the-knot.com/arithmetic/rapid/index.shtml

Fibonacci numbers and the Pascal triangle
   The relation between Fibonacci numbers and Pascal's triangle. English/German/Serbian.
   http://milan.milanovic.org/math/

Gardner Index
   Rough index to the fifteen books containing Martin Gardner's Mathematical Games articles from Scientific American.
   http://www.ms.uky.edu/~lee/ma502/gardner5/gardner5.html

Geometric Packing Problems
   By Joseph Malkevitch: "Given one shape X how and when can one pack identical copies of this shape into another shape Y?"
   http://www.york.cuny.edu/~malk/tidbits/tidbit-geometric-packing.html

HAKMEM
   A collection of problems from MIT. Work reported herein was conducted at the Artificial Intelligence Laboratory, a Massachusetts Institute of Technology research program.
   http://www.inwap.com/pdp10/hbaker/hakmem/hakmem.html

How To Manually Find A Square Root
   The way to do find a square root without a calculator.
   http://math.arizona.edu/~kerl/doc/square-root.html

Iamond
   A page on polyiamond puzzles. Includes many pages on tessellation.
   http://www.mathpuzzle.com/iamond.htm

Look and Say Sequence Generator
   Creates a special kind of summation formula created by John Conway.
   http://www.btinternet.com/~se16/js/looknsay.htm

MAA Library List in Recreational Mathematics
   Book list split into categories. Includes title, author, publisher and date information about each book.
   http://www.maa.org/BLL/recmath.htm

MAT 007 I News
   A newsletter edited by undergraduates of the Department of Mathematics at the University of Toronto. Includes some online copies.
   http://www.math.toronto.edu/007/

Math Forum: 2001 Mathematics Game
   A contest that asks to write all integers from 1 to 100 using only the digits 2,0,0,1 and arithmetic operations.
   http://mathforum.org/~judyann/2001/

Math Forum: 2002 Mathematics Game
   A contest where the contestants have to write all integers from 1 to 100 using only the digits 2,0,0,2 and arithmetic operations.
   http://mathforum.org/~judyann/2002/

Math Forum: Algebra Problem of the Week
   View this week's algebra problem or those of previous weeks.
   http://mathforum.org/algpow/

Math Magic By Computer
   Interactive java puzzles and activities in different mathematical topics.
   http://www.cut-the-knot.org/Curriculum/index.shtml#magic

Math in the Movies
   A guide to major motion pictures with scenes of real mathematics.
   http://world.std.com/~reinhold/mathmovies.html

Mathematical Fiction
   A list of mathematical fictional movies, books, stories, plays and shows. Split into categories including children's books. Can be sorted by mathematical content and literary quality.
   http://math.cofc.edu/faculty/kasman/MATHFICT/

Mathematical Induction
   A page of uncommon problems, most closely connected with number theory.
   http://www.math.cl/induction.html

Mathematical Lego Sculptures
   Designed and built by Andrew Lipson. Images and LDraw files.
   http://www.andrewlipson.com/mathlego.htm

Mathematical Problems - Problem Solving
   Mathematics Hots (Problems) by Bruno Kevius
   http://mathres.kevius.com/problem.html

Mathematical Quotation Server
   A collection of mathematical quotations culled from many sources. You may conduct a keyword search through the quotation database.
   http://math.furman.edu/~mwoodard/mquot.html

Mathematical Spectrum
   Mathematical Spectrum is a magazine for students and teachers of mathematics in universities, colleges and schools worldwide. It may be read by anybody interested in mathematics as a recreation.
   http://www.shef.ac.uk/uni/companies/apt/ms.html

Mathematics Museum (Japan)
   At Mathematics Museum (Japan) you would be surprised how interesting mathematics is. You will find exhibition rooms produced by Japanese researchers and educators.
   http://mathmuse.sci.ibaraki.ac.jp/indexE.html

Mathematics in Art and Architecture
   An interdisciplinary course on mathematics in art and architecture.
   http://www.math.nus.edu.sg/aslaksen/teaching/math-art-arch.shtml

Mathematik
   Individual pages on different topics in Mathematics. Examples : group theory, dynamical systems theory, geometry or number theory.
   http://www.mathematik.com/

Mathematische Basteleien
   Topics include Flexagon, Soma Cube, Pentominos, Cube-it, Rubik's Cube, Froebel's Star, Tangram, House of Santa Claus, Chronogram, Numeric Palindromes, Latticework of Letters. English/German.
   http://www.mathematische-basteleien.de/

Mathmos
   Includes puzzles, jokes, quotations, poetry, and FAQs.
   http://www.mathmos.net/

Maze Classification and Algorithms
   A short description of mazes and how to create them. Definition of different mazetypes and their algorithms.
   http://www.astrolog.org/labyrnth/algrithm.htm

Mudd Math Fun Facts
   An archive of interesting math facts for use in the classroom or just for fun. Browse by subject, difficulty, keywords, or try the "random" feature. Based at Harvey Mudd College.
   http://www.math.hmc.edu/funfacts/

Number Recreations by Shyam Sunder Gupta
   Features interesting facts about different numbers. Includes favorite related links.
   http://www.shyamsundergupta.com/

On the Puzzles with Polyhedra and Numbers
   This is an article on a set of didactical games edited by the Portuguese Mathematical Society (SPM).
   http://gfm.cii.fc.ul.pt/Members/jr_poliedros-puzzles_en.pdf

One Metaphor Fits All
   Explains Conway's audioactive decay that is generated by a particular kind of sequence. Includes illustrations and related resources.
   http://www.btinternet.com/~se16/mhi/

Origami Mathematics
   Information on the mathematics of paper folding.
   http://www.merrimack.edu/~thull/OrigamiMath.html

Properties of Dice
   Polyhedral dice and their properties.
   http://hjem.get2net.dk/Klaudius/Dice.htm

Recmath
   Includes pages on magic squares and polyomino patterns and contains related java applets.
   http://www3.sympatico.ca/diharper/

Recreational Mathematics
   Links collected at CAMEL, the Canadian Mathematical Society website.
   http://camel.math.ca/Recreation/recreation.html

Recreational Mathematics (David Eppstein)
   An extensive list of web resources for recreational math.
   http://www.ics.uci.edu/~eppstein/recmath.html

Recreational Mathematics Forum
   A forum for posting messages about math recreations. Hosted at Delphi.
   http://forums.delphiforums.com/recmath/start/

Recreational Mathematics Topics
   By Steven Dutch. Symmetry, Crystals, Polyhedra and Tilings; Pythagorean triplets and other things about sums of powers; Geometry Classics.
   http://www.uwgb.edu/dutchs/RECMATH/recmath.htm

Roman Numerals
   Contains a introduction to Roman numerals including a translation of the digits used and a converter which can convert decimal to Roman numerals and vice versa.
   http://www.novaroma.org/via_romana/numbers.html

Rubik's Cube Lecture Notes
   Notes on the mathematics of the Rubik's cube.
   http://web.usna.navy.mil/~wdj/rubik_nts.htm

SimonSingh.net
   Home of Simon Singh: author, journalist and TV producer, specialising in science and mathematics. Cryptography is one of his specialties, and his site has a lot of educational and fun content about codes and codebreaking.
   http://www.simonsingh.net/

Sir Roger Penrose
   A article about him and his interests and contributions to recreational mathematics.
   http://www.worldofescher.com/misc/penrose.html

Skytopia - Super Magnet
   A colourful world built entirely using mathematical atoms and molecules. Pictures and animations demonstrate structures colliding and interacting. Animated GIF demonstrations.
   http://www.skytopia.com/project/magnet/magnet.html

Spirocharts
   A windows application that creates mathematically precise spirograph drawings; savable as images.
   http://www.nehuenmultimedia.com.ar/html/spirograph.html

Spirograph
   A java applet for creating Spirograph images.
   http://dogbomb.com/spi/

Stunning Friends with Math Magic
   A collection of card tricks, number guessing games, paper and glue magic, and other math exercises.
   http://www.cut-the-knot.com/arithmetic/rapid/magic.shtml

Table of Numbers Problem
   Given a m * n rectangle, place all numbers from 1 to mn that minimizes the sum of the products of rows and columns (both in Spanish and English).
   http://www.alpertron.com.ar/CUADRO.HTM

The Aesthetics of Symmetry
   A brief digression into how people perceive symmetrical patterns -- what makes them boring, interesting, or overly intricate
   http://home.earthlink.net/~jdc24/symmetry.htm

The Eugène Strens Recreational Mathematics Collection
   A special collection at the University of Calgary, including the archives of Martin Gardner. There is a searchable online index.
   http://www.ucalgary.ca/library/SpecColl/strens.htm

The Nine Digits Page
   Puzzles and problems connected with numbers using the digits 1-9.
   http://www.worldofnumbers.com/ninedig1.htm

Treasure Troves : Book List
   Book list including titles, authors, publishers, prices, page count and some have links to Amazon.com.
   http://www.treasure-troves.com/books/RecreationalMathematics.html

Wade Edward Philpott
   Profile and description of his mathematical games and puzzles.
   http://www.gamepuzzles.com/wade.htm

Wade Edward Philpott Collection
   A special collection at the University of Calgary Library.
   http://www.ucalgary.ca/library/SpecColl/philpott.htm

Who Can Name the Bigger Number?
   An essay by Scott Aaronson on the quest for ever-bigger numbers, from exponentials to Busy Beavers.
   http://www.scottaaronson.com/writings/bignumbers.html