A Sudoku is a number puzzle that is currently taking over the world (at least my neck of the world).

Websudoku lets you play tons of sudokus (sudokais, sudoks?) online, at three different game levels.

The rules of a sudoku are pretty simple: you have a grid of 9x9 and you need to place each digit from 1 to 9 into the grid so that every column, every row, and every 3x3 square must contain one of each of the nine digits.

Totally addicting...