Haha. I am pretty new, but one of my favorites was when I killed the first bandit in the cave outside Seyda and he was just laying there, floating in midair over the fire!
Another funny one was when I was at Balmora, crossing the bridge to the South Wall Cornerclub, and there was this gaurd just walking under the bridge in the water, for no reason. He hadn't followed me down there or anything. It was silly