Processing is one of my favorite visual playgrounds; a community and development environment created to promote software literacy within the visual disciplines (essentially, you program to make visual artifacts).
Lately, my partner Su’s been following Mark Webster, a skilled artist within the medium, and watching his Flickr stream grow with lovely, impressionistic artifacts created within Processing. Add this to your RSS feeds; it’s inspiring work. Mark’s personal site has a wealth of links to follow as well.
(image from Mark’s Flickr stream)