Matthew Geddert guessed that I was shooting these using a digital camera to shoot the focus screen of an older, medium format film camera. In this case, a Richoflex, "Twin Lens Reflex" or TLR (as opposed to a single lens reflex or SLR).
The fun things about these cameras, sometimes known as "view cameras" (as seen in Julie and Julia, my wife tells me), is that you look down into them from above which makes them perfect for mounting a digital SLR or point and shoot onto them with an unweildy and unstable piece of cardboard. They use two lenses because the bottom one puts the image on the film while the top one puts the image on the focus screen. In your SLR, they get around this by having the mirror that reflects the lens image up 90 degrees to your focus screen flip up and out of the way when the shutter releases.
I'm having no end of fun with the grainy, dirty square images it produces. Even more fun is shooting video through it. The shallow depth of field and manual focus makes it feel like old super 8. Hopefully more video to post later.
Update: In the mean time Geddert wins his very own iPod refrigerator magnet. This is essentially an old, broken iPod with a large magnet inside. Impress your friends! I'll mail it or send it via mutual-friend post.