I realised the school PC’s boot order was A:, then C:, booted into DOS from floppy to get behind their own autoexec.bat, installed my own which just repeatedly echo’d “Teachers suck”.

They had some shitty network config utility, which was relying on a weird script language (from a company called BFC Computers). Anyway, it synced some assets down to customise a series of crappy programs with licenses and “Property of Bangsbostrand Skole” messaging. I changed to it randomly (about once a month, across their fleet or 50-ish PCs) retrieve a different set of strings and pictures which all said “Teachers suck”.

I was banned from the computer lab for a year. They fixed the autoexec issue within a day (after calling “very expensive consultants, young man!!”) but when I left some their PCs would still occasionally display “Teachers suck” instead of “property of” in various programs.