1 {Prof. Jones is lying down on the floor in the background}
1 Minnesota Jones: Well, that settles it. We've identified exactly which Arthurian artefact this is.
2 Minnesota Jones: The Knife of Llawfronedd. The magical knife with the ability to carve enough meat to feed 24 men!
3 Monty: How can you be so sure, grandad?
4 Minnesota Jones: Your dad had a little bit of trouble finishing that whole meal!
4 Prof. Jones: {still lying down} I think I'm ready for dessert now.

The Knife of Llawfronedd is one of the Thirteen Treasures of the Island of Britain. Its owner's name is variously spelt as Llawfronedd or Llawfrodedd depending on the source. The latter seems slightly more popular on the net, but I found the former spelling first so I decided to stick with that.

The Thirteen Treasures, by the way, are awesome inspiration for interesting magical items in fantasy roleplaying games. Which really just goes to show that Early Middle Ages Britain really was just one big game of Dungeons & Dragons, just as we always suspected.