Foster and Partners is known best for its unconventional architectural projects, including the under-construction Apple headquarters, which, because of its circular shape and mile-long circumference, has been likened to a giant spaceship. The British firm has also dabbled in boat design, creating vessels that are as distinctive as its buildings. It worked on the interior of the Perini Navi sailing yacht Panthalassa, using light colors, windows and skylights, and an absence of clutter to make the below-deck spaces seem larger than they are. Foster and Partners’ latest boating project is the Alen 68 by Alen Yacht (www.alenyacht.com), a collaboration with the Turkish shipyard. Not surprisingly—considering that the model line’s prototype, christened Iguazu, was built for the owners of Panthalassa—the Alen 68 also features a lack of clutter on the deck and below. The boat maker claims that the design, compared to those of comparably sized yachts, creates 20 percent more space. The Alen 68 has a base price of about $3.7 million and a top speed of 44 knots.