I used to have one of these and used for field work. A little story from the past:
I used to stick the calculator in my crotch. I had to or it would be too cold to read the little magnetic cards it used. It was a Hewlett-Packard, pretty fancy, and it used those little gray cards to store programs on. They were about a quarter inch wide and and two inches long, thin and they would seize up in the card reader if anything got too cold.
I tried using my armpits but that never worked as well, so the crotch it was. I had to warm up the stove too but it’s the calculator I remember. It used rpn which stood for Reverse Polish Notation, and a stack. You had to put everything you wanted use in a formula into the stack. You’d push them up, then they’d ride down as you did the calculations. It was a lot like skiing - you’d push yourself up, and then you could ride down. And that was how I got to my study area - push myself up and after a week or so I could ride down hill. This study area was close to the road, only 7 miles in. Or seven miles up, I guess. It was a nice ride going down, as long as you didn’t fall. If you fell and got hurt, you died. You’d die alone and cold, but I never thought about that.
I also used it when it was too much trouble to go down the hall and log onto the mainframe. One of my awards during my graduate career was for force-feeding a distributed parameter model into the mainframe. I was lazy and just used nested Do Loops. One night I killed the Andahl 470 mainframe with it. I was worried the Sysops would hunt me down so stopped running it for a while after that.
The other tripod leg of research was laboratory studies. I thought the gear we used was very expensive until I found out that some of it just had "Medical" stamped on it and then sold for 3x the price with no changes and no additional testing.