.... I used to run a monthly payroll for 1200 employees on a machine (Univac 1004) with 2k of memory. The master file was on white punched cards, with variable data for one month punched onto red cards, then card-sorted into the master file. Next month, the data was on blue cards. So you could see from the other side of the room the status of the file.

Prior to that, I used the Deuce with mercury tanks for memory - you put a sound pulse in, counted 32 machine cycles, and then put the sound back in if you wanted to remember it. With several of these, you had 32 bit Words to play with.... I still have the user manual somewhere....