A comeback used when people that think of themselves as popular or cool make a lame one-liner and think it's the funniest thing since "I'm on a boat," when in reality you aren't affected at all.
Derived from those teen movies in the 80's when the bitch and her best friend/follower make a cheesy remark, usually followed by a high-five, or something of its equivalent.
New Girl: Who are they?
Friend: They're the most popular girls in school... Oh crap, they're coming this way! Quick, look away!
Popular Girl #1: What are you looking at geekface?
Popular Girl #2: Yeah, geekface!
New Girl: Wow, you're so lame circa 1985!