Having an idle and quite old second-hand Wacom Tablet, I'm easily always away from my PC. A friend of mine recommended Phidias which happens to be a paint program sort of like MS Paint in Nintendo DS Lite. To my surprise, with almost a week ago of trying to make the brush work, I saw an article that says you just have to put the "brushes" folder under the Phidias folder of your MicroSD card and voila! You're on the go for DS painting experience!
Here is an example of my first attempt at the program. I already converted it to jpeg format anyway. The image is about 512 x 384 in resolution which happens to be the largest resolution for Phidias as of the current release which is Phidias041907.