The Pan-NO-Head by BVR which (if I read this correctly) helps to make it possible to do a panoramic print with a digital camera and an 8mm fish eye lens.

The description includes a series of letters (npp/lpp/osp/GR) that may mean more to 'pano-heads' then it does to me but you can check out the process and the interactive images on the Buffalovr site.