XPLANE offers XPLANATIONS
XPLANE is a company whose whole purpose is professional infographics. They do a bunch of infographics for big and small companies, but also do a lot of work for Business 2.0 magazine (a favorite of mine). Check out David's post that Business 2.0 might be in trouble.
A number of infographics (called XPLANATIONS...I love it) are available free for download here.
David Grey is the CEO, and he also runs his own blog called Communication Nation.