I just played around with this program which I liken to Tux Paint's big brother. Sumo Paint allows a trial without download which I rather like since I seem to fill up computers rather quickly. There were some neat features I hadn't seen before including a kaleidoscope-like button that, well, works like a kaleidoscope. Their term for it is the Symmetry Tool. Love it!
It also allows you to see other people's work and share your own. The capability to comment on other's work gives a social networking component to the program that others lacked and make it more popular. Give it a try!