Include news, math tricks, methods, facts, trivia, mostly posted by users.

Individual pages on different topics in Mathematics. Examples : group theory, dynamical systems theory, geometry or number theory.

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.

Includes puzzles, jokes, quotations, poetry, and FAQs.

Features interesting facts about different numbers. Includes favorite related links.

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.