Well, it's kicking off again. We had a "Submarine" prowling the shallow waters in the Stockholm archipelago some months ago which turned out to be a wooden pier that was drifting with the currents.

Now we have this film shot outside of Gothenburg showing a fisherman's buoy being pulled by something, be it animal, current or sub, speculations are running wild. Your thoughts? (Ignore the article in Swedish and watch the movie at the top).
http://www.aftonbladet.se/nyheter/article13636869.ab