Harmony by Mr. Doob : Draw from your browser sketchy, shaded, chrome, fur, long fur and web style.
Keystroke : Applications with multi-user/multimedia features
GrafX2 is a bitmap paint program inspired by the Amiga programs Deluxe Paint and Brilliance. Specialized in 256-color drawing, it includes a very large number of tools and effects that make it particularly suitable for pixel art, game graphics, and generally any detailed graphics painted with a mouse. The program is mostly developed on Linux and Windows, but is also portable on many other platforms.