The anthem of the Ghetto Revival.
Ben: "Yo, this place is perfect for the Ghetto Revival."
Clem: "Hallelujah hollaback!"
Separately, hallelujah means praise the Lord, while hollaback means reply. So, combined, it means praise the lord for answering my prayers. Usually used when the Lord sends a fine piece of booty across your field of vision.
Leeroy: Daaaaaaaaammnnn look at that fine piece of booty...
John Brown: Hallelujah hollaback!