Turducken is a dish which is made by stuffing a de-boned chicken inside a de-boned duck which is subsequently stuffed into a turkey which is de-boned except for the legs and wings. Sometimes Chef Paul Prudhomme is credited for this creation while others credit John Madden, ex football announcer and football player.
You can find recipes for making your own online here. You can also purchase frozen versions of this roast in specialty food stores as well as online at Amazon.com: Turducken