Creative puzzles
Creative puzzles
http://www.creativepuzzels.nl/
Math Puzzles Ed Pegg
Math games, math puzzles, and mathematical recreations
http://www.mathpuzzle.com
Problem Corner
Problem Corner
http://faculty.missouristate.edu/l/lesreid/potw.html
Sudoku
De nederlandse site over sudoku. puzzel van de dag, uitleg voor beginners en gevorderden, online puzzelen, sudoku per sms
http://www.sudokunet.nl