Towing both a trailer and a boat at the same time sounds impossible, but here's a clever solution. The Sealander allows you to go boating on your camping trips by rolling both types of vehicle into one somewhat odd looking trailer.
The German made camper looks pretty minimalist as either a trailer or a boat, but I guess it's okay if you're the type of camper who travels really light. A small electric motor will push you around once you're in the water, and because the Sealander weighs only around 840lbs, so it should be pretty easy for any car to tow.
While it might work for skinny Germans, I'm not sure if most Americans would find the Sealander's capacity to be sufficient. Over here we tend to prefer something a bit larger.
The Sealander will be available next year for about $20,000.