Interesting that this is on the eve of Apple's launch of the supposedly revolutionary tablet, but anyways; I've been playing with Autodesk's Sketchbook Express on the touch, and it has been a pretty solid painting tool so far. Drawing on a touch device is definitely harder than drawing on a tablet, mostly because your finger is constantly in the way, and there is no hover indication exactly where the brush is going to be (the touch display on the touches are capacitive). Though on the other hand, the zooming, color picking and marking menu gestures are natural, and the ability to rotate the device at a whim makes the process much nicer than it could have been. I'm not sure what the free version of the app is missing, but so far, it seem to have everything I would need when drawing/sketching something down on the go. Ironically, I have also learned that I can draw a circle with a pen much easier than I can draw one with my finger... maybe I'll just blame it on the train ride.