20 Years of Photoshop
benwiggy writes "Photoshop turned 20 on 10th February 2010. Here's an excellent history, including how the Knoll family created one of the biggest apps of all time. The article also has screenshots of the workspace through the versions."
I've had a lot of luck with Krita.
Dewey, what part of this looks like authorities should be involved?
Yes, we are: interim results at http://wiki.koffice.org/index.php?title=Krita/Benchmarking and weekly updates at http://www.krita.org/ Boudewijn Rempt -- Krita Maintainer.
The article leaves out quite a bit of the history of digital paint programs. This article contains a good summary (although it also leaves out yet other work).