A drawing tool that works off the principle of how light color works (adding colors together gets you closer to white, as opposed to what we're used to with crayons getting closer to a muddy brown).
You can also view "replays" of other peoples' creations, so you can see how they drew it. Here's my drawing something on my lunch break: http://r.weavesilk.com/?v=4&...
CryptoPoops