I just had to solve a captcha that was a bunch of pictures of objects and it says "Select all the objects that can not spin"... I'm just thinking "My dude, anything can spin with if you put enough energy into it"

@freemo My favourite was when the European Space Agency rolled their own security questions on a new satellite data portal a while back. The questions were a mix of changeable answers ("When did you last water your plants?") and yes/no answers. The minimum field length was three characters.