Get this!
Definition 1 of 1
Pro Tip 1/3Attention Grabber
Use 'get this!' to emphasize that what follows is important or unexpected. 
I was so bored, and then, get this, a celebrity walked into the room!
Pro Tip 2/3Colloquial Use
'Get this!' is casual and typically used in informal conversations among friends. 
So, get this, she got a tattoo just like the one you were talking about!
Pro Tip 3/3Surprise Element
It often introduces information that is surprising or not widely known. 
They found an old safe in their backyard, and get this, it was full of old coins!