Madcow,
I too worked with the UYK 20 by Sperry Univac as a Navy Fire Control Tech. I remember well punching in data a few bits at a time. In my application the program emulated the old analog MK 47 Gun computer; gears, synchros, servos, ball and disk integrators, resolvers, tube or transistor amplifiers, and many dials and hand cranks. All this to put a bullet in the same space as a target at the same time 12 miles away. Taking in consideration; ships movement, target movement, projectile initial velocity, winds, fuse time, and earth's rotation. Quite an accomplishment in it's time.
Just a little history of the roots of modern computing.