This is a way of sarcastically saying no way?! or really?! or of Course!...but it is completely sarcastic so you dont even have to have a tone with it. The word speaks for itself.
This phrase thrived during the late eighties to early nineties in elementary schools through high schools. It is a way of saying "I already knew that, and am surprised this information is new to you."
I don't buy the schmegegge about Morty sleeping with Moira.
His version of the story was pure schmegegge.
The whole schmegegge was made up to get Liz a little bit of attention.
Looking or experiencing something nice after witnessing something horrid like a disgusting gif or a disturbing video. Typically used as eye bleach are nice images of whatever makes the disturbed person happy.