Space Cadet keyboard

This keyboard was originally designed for the Plasma Fusion system, as well as MIT LISP machines. It was sold with the early commercial LISP machines, such as those from Symbolics.

One of the explanations for the baroque collection of keys on this keyboard was that it was designed by committee, and that no suggestion was rejected. I actually think that more thought went into the design than that. Still, many of the user-interface ideas behind certain key additions never materialized in actual software systems. So, it remains a monument to design excess.

Later Symbolics machines has a low-profile ("ergonomic") keyboard with a much more modest assortment of keys, specifically designed for use with the Genera system, plus the infamous Square, Circle, and Triangle keys. See here for a picture.

Some interesting things to note about this keyboard:

Overall view

The home keys

Front legends

The circuit board