SMJ

It means Shake My Jesus. An Alternative to SMH. Usually pronounced with the voice of Jeremy Clarkson

Dude 1. "Dude dave did it again"

Dude 2. "SMJ"

Muckelspäck

Is when your best friend does something silly or stupid to an inanimate object or when a friend does something to you that has offended you. Can also be used as an insult.

Man1 "That ball is so stupid it does not do what I say."

Man2 "Wow you are such a muckelspäck."

Man1 "Stfu you are such a pussy

Man2 "Better watch your mouth or im gonna muckelspäcka you"