Mercedes' S-class is a wonderful land yacht, but it is most emphatically a land-only yacht. If you drive one into the water, it will not work even a tiny little bit. Trust me. However, if you wish to take your Mercedes-Benz experience on the open seas, then good news: they'll now sell you an actual Mercedes boat.
Well, sort of. The Arrow460-Granturismo motor yacht isn't a full Mercedes offering, but rather a collaborative effort between Mercedes' styling division and Silver Arrows Marine, a UK-based boatbuilder. Considering that Mercedes has traditionally called their racing teams the Silver Arrows, there's a nice dovetailing of names here.
The Arrow460 features styling reminiscent of the S-Class and Mercedes tech like the electronically-dimming windows. It's a gorgeously swoopy thing, polished like the spaceship from Flight of the Navigator. Twin turbodiesel engines pump out a generous 960 hp, and are capable of propelling the craft to a stately 75 km/h top speed. Normal cruising speed is more like 50 km/h, and if that seems slow, remember that you don't need to wear a seat belt and there's no traffic off the Cote d'Azur.
To bring things back to dry land, it's worth pointing out that we haven't yet seen the rumoured-of latest iteration of the S-Class, a coupe-styled four door. Best guess is that it'll look a lot like the Arrow460. Only, you know, with wheels.