I agree that the early 90's were a lot of fun – I remember drilling holes in 3.5-inch floppy disks to increase their capacity, blissfully unaware that actual HD floppies had a different coating entirely…

Two (of the many) mind-blowing discoveries of the 80's:

1. there was a disk notcher (the Nibbler?) that would DOUBLE the capacity of a 5 1/4 floppy!

2. you could just use a regular paper hole punch and a few select clips to do the same thing!

All my C64 floppies had faint parallel pencil lines across the top to line up the slots and what looked like mouse-nawed holes on one side.