Sometimes, a casual conversation over drinks produces the best ideas. Yacht designer Doug Zurn had joined Matt Elder and Pat Shannon, partners of Inland Sound Yachts in Port Townsend, Washington, to talk about a new design. Over drinks, ideas floated above the table like spirits at a séance. Zurn plucked a handful of these out of the haze and sketched on a cocktail napkin. He massaged that doodle into the Inland Sound 48 — a handsome, roomy and seaworthy yacht that promises to be fast, economical and easy to operate and is geared to the varying needs of families.