I sort of had a stalker a few years ago. It may have been just a friend playing a prank, but to this day none of my friends will admit that it was them, so maybe it really was a stalker.
This person called my work all the time, pretending to be my girlfriend (I didn't even have a girlfriend at the time) and asking if I was working that day.
By some weird coincidence, the person only called on days that I wasn't working, so I never actually spoke to them on the phone or saw them in person (as far as I know). It went on for a few weeks, just long enough for me to start getting a little worried, and then it stopped as mysteriously as it had started.