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

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

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

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

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/

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

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

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

Final Answers
- Numerous facts including formulas, magic tricks, fallacies, recreations compiled by Dr. Gerald P. Michon.
- http://home.att.net/~numericana/answer/

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

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

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

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

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

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

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

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/

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/

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/

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

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

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

The Diamond 16 Puzzle
- New version of the classic puzzle using row/column/quadrant permutations to display symmetries of graphic designs. Has link to a site on the underlying mathematics (Diamond Theory).
- http://m759.freeservers.com/puzzle.html

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

A Mathematician's Aesthetics
- In his classic A Mathematician's Apology, G. H. Hardy likened mathematics to poetry and painting. This site elaborates on Hardy's remark with quotations from Stevens, Klee, Fry, and Focillon. Links to related sites are given.
- http://m759.freeservers.com/PHaesthetics.html

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

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

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

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

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

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

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

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

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

Recreational and Educational Computing
- A newsletter with programs, including optional supplemental PC disk. All back issues are available. Topics include puzzles and teasers, BASIC programming, letters, graphics, fractals, challenges, recreation, reviews, word-play, humor, tips, solutions,
- http://members.aol.com/DrMWEcker/REC.html