A free, Open Source drawing program for young children (ages 3 and up). It has an easy to use and fun interface. Along with standard drawing tools, like brush, lines, shapes and eraser, Tux Paint also has multiple levels of undo and redo, a collection of "Magic" special effect tools, a "Rubber Stamp" (a.k.a. "Sticker-Book") tool for placing pre-drawn shapes and photographic objects into a picture, and "Starter" images that provide coloring book imagery and scenery to paint on.
Tux Paint has been translated to over 55 languages, including Spanish, French, German, Italian, Greek, Hebrew, Chinese, Japanese and Korean. It is available for Windows, Linux, Mac OS X and BeOS and other Unixes.