sudoku me insane...

numbers one to nine

nine little boxes of nine

nine by nine is... NEIN!

~

数独

Have you tried SUDOKU yet?

Wikipedia defines it as:
(Japanese: sūdoku), sometimes spelled Su Doku, is a logic-based placement puzzle, also known as Number Place in the United States. The aim of the canonical puzzle is to enter a numeral from 1 through 9 in each cell of a 9×9 grid made up of 3×3 subgrids (called "regions"), starting with various numerals given in some cells (the "givens"). Each row, column and region must contain only one instance of each numeral. Completing the puzzle requires patience and logical ability. Its grid layout is reminiscent of other newspaper puzzles like crosswords and chess problems. Although first published in 1979, Sudoku initially became popular in Japan in 1986 and attained international popularity in 2005.

Do a Google search on the word Sudoku and you will find LOTS of puzzles.