Facebook-off
A virtual war taking place on facebook. Can arrive in the form of flame wars, poke fights, etc.
"God damnit, Jim won't stop poking me! I declare a facebook-off."
Facebook rip-off
Someone who appears more beautiful on his/her facebook profile picture than they are in reality.
Dude A: Dude, Jennifer isn't as hot as you told me she is!
Dude B: Dude, that was totally a Facebook rip-off.
Dude B: Dude, that was totally a Facebook rip-off.