Sudoku - Numbers-based Game
Sudoku is a numbers-based game. The rules are simple -- players attempt to fill in a nine-by-nine grid before going completely insane. Not surprisingly, these brainteasers owe their existence to a mathematician.
Leonhard Euler is widely acknolwedged as the father of Sudoku. In 1793, Euler invented "Latin Squares," the precursor to today's modern Sudoku puzzles. As far as mathematicians go, Euler was pretty famous in his day. According to about.com, the "Swiss genius dominated 18th-century mathematics."
The name Sudoku didn't come until much later (1984, to be exact). According to the London Observer, a Japanese publisher made a few logistical improvements to the game and then dubbed it "Sudoku." In Japanese, "Su means a number and doku roughly translates as singular or unique," says the Observer.
These days, you can find Sudoku games all over the Web.