d00n
See n00b, when looking at d00n backwards it is n00b, is often used to confuse newbies.
Person1: OMG I AM TEH ULTIMATE G4M3R!!!!11112121212
Person2: The only thing you are is a d00n
Person1: OMG WTF IS DAT!?!!?
Person2: The only thing you are is a d00n
Person1: OMG WTF IS DAT!?!!?