I never use pause break, scroll, home, page up, page down, and end keys. I don't even know what those are for!
I never use the pause/break button, or the pg up and pg down buttons. I didn't even know they were there 'till I checked my keyboard to answer this thread!
Back in the old school days, they were used to send system commands to the mainframes. Some programs now use them for doing things like help menus, shortcut keys and the like.
That's a good question that I had never realized. I never use "Prt Sc SysRq" I know is for printing but never used.
Insert because it quite simply annoys me. My laptop likes to click in random chunks of editable text, so I end up writing over it. I wrote myself a macro script so that whenever I press it, it will automatically turns it off again.
I think that is quite strange. I always use ~ to denote an average or estimation. "I'll be out in 10 mins~" People never ask what it's for they just understand.