Webum > Games > Puzzles > Brain Teasers > Mathematical See also Science > Math > Recreations > Games and Puzzles Dave's Logic Puzzles Monthly logic puzzles with solving grids. Flooble: Perplexus A forum and collection of brain teasers, logic problems, math problems, paradoxes, science games, probability, riddles, and geometric shapes. IBM Research: Ponder This Monthly logic and math puzzles set by IBM researchers with solutions. Jim Loy's Puzzle Page Classic and original puzzles. Leisure Ideas: Puzzles Some mathematical puzzles with answers and/or a hint. TechInterview Answers to technical interview questions, programming problems, and brain teasers. The Pyramid Contains a collection of progressively more difficult problems. The more challenging problems require more than just mathematics to solve. The Truth Tree's Math and Logic Board Collection of math and logic puzzles ranging in levels of difficulty. Help build the biggest human edited directory on the internet Add your website - Open Directory Project - Become an editor