I'd second the one about work laptops having powershell scripts for whatever the IT wants them for. However if it's your personal property then it could be just about anything, maybe something innocuous you've installed that you wnat but maybe something malicious..
Personally, I'd take this as a sign to do a fresh install of the entire OS. That can feel like a chore, sometimes, but it's the best way to be nearly absolutely sure your computer is clean.