Comes from the MC Hammer song but is now commonly used for when someone says
something annoying and you want to express your anger with someone
you know.
It now means to beat someone to death with a hammer. Lovely
Danny: I get £10,000 when i'm 18 so upset I
have to wait, damit!
Jonzy: *To Dave* Hammer Time! *With fist action of
smashing down Danny with a hammer*
Dave: *To Jonzy* sum1 goes
I care or sumthin