Darth Vader is having a light sabre fight with Luke Skywalker, suddenly he backs off and says,
“Luke, Luke, I know what you’re getting for Christmas!”
“No, father, you don’t!” says Luke, “Now I must fight you.”
“Luke…” says Darth, backing off a bit more, “I KNOW what you are getting for Christmas!”
“No, father, you don’t.” says Luke, “Now are we going to have this fight or what?”
“Do not under-estimate the Dark Side, my son, I know what you are getting for Christmas!”
“No you don’t, father." replies Luke.
“Yessss, my son, I do for I have felt your presents.”