http://mypaint.org/MyPaint is a Free and Open Source art software that focuses on distraction-free digital painting, with lots of keyboard shortcuts and a minimalist expanding canvas. It's great for sketching, but I've also seen some truly beautiful professional works done with it!
It's available for Linux, Windows, and Mac OS X :D
Check it out, and please share your #
MyPaintArt creations!
#
ArtWithOpenSource