From GameBrew - a wiki dedicated to Video Game Homebrew.
A stereogram drawing application for the Nintendo DS. Draw-stereo is a toy which allows the creation of stereograms on the Nintendo DS.
The DS screens are spaced appropriately for cross-eye stereogram viewing. For best results, use in a darkened room, and hold the DS at a comfortable distance for drawing (18" or so).
Hold the DS like a book. The illusion can be quite effective. Enjoy!
Up/Down - pen elevation +/- 1px
ABXY - reset elevation
Select/Start - clear screens
L/R - swap screens (reverses depth)