well chuffed

One of my British coworkers introduced me to a new term (for me): chuffed, or well chuffed. It means to be happy with oneself.
http://www.urbandictionary.com/define.php?term=chuffed

Usage:
Yesterday, my boss promoted me to senior technical peon. I'm well chuffed.

People, it's time to assimilate this into the vernacular.