Interactive Math Miscellany and Puzzles

Interactive Mathematics Miscellany and Puzzles This as a fabulous Mathematics site with a huge collection of the basic mathematical principles used in Arithmetic, Algebra, Geometry, Games and Puzzles, Logic, Fractals and chaos, Probability, Calculus and Computers. The site is very interactive, the theory nicely presented and well organized. Free, Found at http://www.cut-the-knot.org/index.shtml