You're in the office, it's midafternoon, and that sweet tooth starts clamoring for attention. A thick, creamy, fruity drink would quiet the ruckus, but you don't want that artificial stuff the fast-food joints peddle. It's too far to drive to the farms in Homestead to get the real thing. The alternative is this roadside stand just south of U.S. 1. Take your pick of fresh papaya, mango, or kiwi juice, or mix and match to create a new concoction. Nonfat frozen yogurt keeps the calories down, and a scoop of protein or ginseng can be added for a boost of energy. Price is on the high side at $4.25, but think of all the gas you're saving. You can get your fix between 9:00 a.m. and 9:00 p.m. Monday through Saturday.