You're
A word that can turn anything anyone says to you into an insult or comeback. However, this is one of the lamest comeback techniques ever.
Normal person: That girl's hair is so ugly
Lame-ass: You're so ugly

Normal person: I love this song!
Lame-ass: You're a song

Normal person: What's the math homework?
Lame-ass: You're the math homework.

Normal person: His father is a bus driver
Lame-ass: You're a bus driver