Cartoonbrew posts some links about the 11th Annual Sketchcrawl, held all over the world, this Saturday, September 23, 2006.
This is all very democratic. Anyone, regardless of skill level, is welcome to devote a few minutes or hours to recording that day visually. There's a forum and a blog and a Flickr site.
Check out the always excellent Cartoonbrew site for more information.