Tomodachi released an homebrew game of the massively popular puzzle game Sudoku. Heres some information from the readme:
· Execute launchSudoku.gpe to play Sudoku.
· Use the following controls:
Joystick: Move the cursor of the board.
Y/X: Move the cursor of the numbers bar up/down.
B: Put the selected number in the selected cell.
A: Empty the selected cell.
L+R: Exit.

Download Here --> http://gp2x-emulation.dcemu.co.uk/sudoku.shtml