My favorite was Lotus 1.2.3. on VAX/VMS. I themed the range names so that reading a block of them told a story. It was a massive program that I later had to write again from scratch with Virtual Basic for Applications.
:) I still manage OpenVMS for a defense contractor doing flight testing. OpenVMS on Itanium, rock solid. People don’t realize that most stock markets around the world still use VMS to process your stock transactions :) Been doing this the early 80’s....IVAXMAN :)