Finn was in the bath tonight, and after I'd scrubbed him head to toe, he'd done his standard "swimming" (crawling with as much splash power as he can muster from one end of the tub to the other. Rinse, repeat.) I pulled the plug to drain the tub. I placed the plug in it's usual spot on the side of the tub. Finn took the plug, and put it back in the drain. This. Was. HYSTERICAL to him.
He's such a beast. :)