Abysmal Vapor said:"Knock off your socks" makes laugh everytime i read it .. I don't know where is the root of that phrase for sure but...
Army duty was mandatory few years ago here and guys who went to serve their duty were joking abour the low hygien . They joke that their socks are getting so dirty and hard that you can actually knock on it and it keeps the shape of your feet after you pulled it off you leg . There are even rumors of a rookie that has been beatien by its officer with one of those socks and got in the hospital from the trauma .
Hahaha and ewww..