Hi, my name is Jake, and I yawn like a wookiee. This hasn't always been the case, but for the past couple years my yawns (and still not all of the time, but it seems to be more often than not nowadays) have born an erie similarity to Chewbacca's throaty growl/howl.
I wish I could claim this as a "talent", but it only works for me involuntarily. I can recognize the onset of a Chewie yawn and play it up or prolong it a bit, but I cannot for the life of me produce the sound on command. I know there are many people on this planet who can; I'm just not one of them.
It baffles me as much as it amuses my co-workers.