Jane Pauley hosts our annual special broadcast about design. In our cover story, Luke Burbank looks at a plan backed by Silicon Valley billionaires to build a new city in California. Also: Seth Doane reports on the construction of a medieval castle in France; Serena Altschul looks at the history of baby strollers; Lee Cowan takes a ride in a $3 million car; Martha Teichner meets the country's most acclaimed maker of weathervanes; Nancy Giles checks out some extreme tie-dye; Jonathan Vigliotti sits down with actress and entrepreneur Courteney Cox; Kelefa Sanneh investigates the rising popularity in bidets; Martha Stewart gives tips on throwing a garden tea party; Conor Knighton meets the man behind Leatherman Tools; and Susan Spencer enjoys fun and games with Wordle, jigsaw puzzles, and the board game Monopoly.