Shareware game based around an extension of the game of life.

Contains print-out and interactive versions. [English and German.]

Monthly logic puzzles with solving grids.

Monthly logic and math puzzles set by IBM researchers with solutions.

Classic and original puzzles.

Some mathematical puzzles with answers and/or a hint.

Information on polyominos and square puzzles.

JavaScript example of the Monty Hall Game. This game demonstrates the real (empirical) affect of statistics. [Does not display correctly in all browsers.]

A forum and collection of brain teasers, logic problems, math problems, paradoxes, science games, probability, riddles, and geometric shapes. The puzzles are searchable and categorized, most have solutions.

Use the clues provided to deduce the correct sequence of numbers in the hidden code.

Tangram which creates hundreds of birds including geometry, tasks, solutions and downloads.

Answers to technical interview questions, programming problems, and brain teasers.

A probability theory puzzle with solutions. [English and German.]

Contains puzzles and games with solutions.

Collection of math and logic puzzles ranging in levels of difficulty.

Describes aspects of a critical problem and apparent paradox in probability theory.

Claims that the two envelope paradox comes from the incorrect use of probabilities.

Discussion board hosted at Berkeley with talk about a variety of solved and unsolved brain teasers.