I love "ta gueule" - gueule means the throat of an animal, so yes it is rather rude. But apparently frenchies use it quite often so it is rude but used so often as to not have the impact it used to have. Kind of like calling people a bastard..... it is rude if your tone says it is rude.
astap - a cet apres-midi
a plute - a plus tard
chepas - ah ha, that explains your name... that's pretty cool indeed
