This Ultimatte frame from a commercial for Bagelman Restaurants shows our two characters and the dreaded giant bagel, which the baker has just rolled into the frame.  In a moment, he will topple it, apparently falling on the spokes.   But the spokes was standing in exactly the right place to go through the hole, and nobody's killed.

In this Ultimatte frame, our spokes beams into the computer's internal workings to explain the fine points of modem supervisory software made by General DataCom.  Sometimes, he beams back out to a miniature desktop size to make some points.  He works the mouse with his foot.

Jack Dahlby is able to put his waxing can down on the antique UPS truck's radiator by putting in down on a blue box on a blue stage. 

The old truck is a polaroid still shot forming the background.

Simple is good.

The Answerman is a tiny super-hero guy who explains the fine points of insurance industry actuarial considerations.  The computer keyboard is rigged with monofiliment fishing line so it can move as our hero hits it with his real 6-foot long pencil.