This house may look a bit strange, with its faux-Asian tile roof and square shape, but the Pagoda Boathouse has some wild and intriguing features. It's on an island in the Detroit River in Grosse Ile, Michigan. Sure, it's got a boat dock, but go down to the basement and find two other docking points inside the house! It also has an escape tunnel that leads across the road to the horse stables, plus secret rooms and passageways. Oh yeah, and servant's quarters with an extra kitchen. Oddly, one of the four bedrooms is only accessible through the bathrooms on either side (the purple one or the green one), but maybe that was designed to be a baby nursery. The interior has been preserved in all of its 1930s glory.
The home is historic, and you might call it notorious, too. It was built by the Ford Motor Company for Henry Ford and his wife Clara. The Fords never lived there; they gave the home to Harry Bennett, the head of the Ford company's union-busting department, for his own security. The house itself has a section on Wikipedia. Bennett moved between several houses in fear of the United Auto Workers, particularly after the Battle of the Overpass.