The addiator is the coolest thing I've ever seen. I found it while I was looking around inside my grandfather
's desk, which is actually a wagon
with a piece of glass
put across the top to form a horizontal surface
. This way, things like decorative tools
and other items can be stored inside, yet remain visible
It was used by my grandmother in her days among the office peons. It has six columns of small gears, and is divided horizontally into positive and negative sections. A row of changeable numbers is located between the positive and negative sections. One uses a small metal stylus to move the gears up and down, thus gaining the ability to add and subtract numbers of up to six digits.
If I had to give up either the addiator or my TI-85, the addiator would win, hands down.