That’s 2 Nikon D90s rigged to be about the same distance apart as the human eyes.
The Stereo Portrait Project was put together by Alex Fry and Jamie Nimmo. These guys assembled the custom rig shown above to capture Anaglyphic 3D images. They’ve even put together a book featuring their 3D images.
Head over to Nikon Rumors for a full rundown of the setup and art behind the Stereo Portrait Project.