Cinematographic camera rig system, mainly implementing focus tracking.
See also: http://atommuell.mum.jku.at/~aurel/focustracking/
Thesis: http://atommuell.mum.jku.at/~aurel/cinefocustracking.pdf
From Wikipedia: The beholder is a fictional monster in the Dungeons & Dragons fantasy role-playing game. It resembles a floating orb of flesh with a large mouth, single central eye, and lots of smaller eyestalks on top with deadly magical powers.