I remember one of the more esoteric applications of binary patching I had to do was to get a bunch of DOS utilities available for an older version running on a newer version, since they had somehow decided to hardcode a versioncheck in them. I used a text editor in binary mode to do it, entering the bytes using Alt+nnn on the keypad.

Thanks to that, the sequence 180 48 205 33 is now embedded in my memory, as is the number 144, and I've acquired the ability to literally read x86 machine code in ASCII. That's a skill that is probably not much more useful than memorising digits of pi, but it's fun to see the reactions of experienced developers when I open some executable in Notepad and start mentally disassembling it.

I've bypassed a few protections too, but probably have spent more time on tweaking various software to my liking. Correcting spelling errors in messages, adjusting UI elements, removing useless messageboxes ("Operation complete! Click OK to continue."), etc.