This happened Monday in Posio, Lapland, Finland. Half a dozen swans were resting by a lake unaware they were being closely monitored by a cat through the window of a house close by. The cat finally decided to sneak up on them in a surprise attack. Of course the swans took off immediately, with the cat on the back of one of them! The owner couldn't obviously believe his eyes and wasn't sure he'd ever see kitty again, but a while later it showed up soaking wet and totally humiliated.
link in Finnish: