Specifically originating from the second Booyah! Lan Gamers lan meet of 2005, when playing Call of Duty 2, players were encouraged to use a video capture program called 'Fraps' to capture particularly impressive 'Killcam's'.
Players who scored an impressive kill would then text chat or sometimes rise from their seat and shout Frapthatbitch!, or equivalent, to express their joy at a well deserved kill.
Sometimes used as a replacement for Pwned or Booyah.
* Player 1 scopes battlefield with sniper rifle
* Player 2 sneaks up behind player one and bashes them to death with butt of their rifle
Player 2: 'ZOMG! Frapthatbitch!'