To this day my dad still runs a stock control program on MS-DOS 6.22. It does the job and never crashes. For a while he had a lovely orange display with a Hercules video card.
> There are many scientific groups where even today, no form of version control is used, even for internal work ...
Where I work (government research lab) people think of Subversion as a sporadic backup target, typically doing a commit every month or so, despite making frequent changes to operational code.
Paradoxically, one scientist I spoke to was scared about overwriting code if he did an incorrect commit, but he's perfectly happy to have mycode.py, mycode2.py, mycode_this_one_works.py, mycode_this_one_works3.py, ...