I've been working on this script in the last few days, and although it's not so small, I believe it can serve a few coding examples and provide some fun.
It's idea is simple: It reads an image, makes it b/w, and using the mouse it draws this image. I made this to draw images on handwrite messages in MSN, but it can be tested in Paint or any other image editor.
The image processing is done by capturing the image, and using the GetBitmapBits API to get the pixels' colors. Based on the pixels color and the set sensitivity, it will be either black or white (the black part is the one that is going to be drawn).
The drawing was a little bit harder to get working on big images. To make it look more like drawing than like printing, the script draws black areas using recursion. In big areas this would overflow the call stack, so I use an array as a custom stack. The random drawing pattern is my favorite.
This is practically useless, but I have a lot of fun using this in MSN. But people don't believe I draw that good...