Private rental outfits include Boat Rental Plus, 2400 Collins Ave., Miami Beach (tel. 305/534-4307), where 50-horsepower, 18-foot powerboats rent for some of the best prices on the beach. There's a 2-hour minimum and rates go from $100 to $500, including taxes and gas. They also have great specials on Sundays. Cruising is permitted only in and around Biscayne Bay (ocean access is prohibited) and renters must be 21 to rent a boat. The rental office is at 23rd Street, on the inland waterway in Miami Beach. It's open daily from 10am to sunset. If you want a specific type of boat, call ahead to reserve. Otherwise, show up and take what's available.
Club Nautico of Coconut Grove, 2560 S. Bayshore Dr. (tel. 305/858-6258; www.clubnauticomiami.com), rents high-quality powerboats for fishing, water-skiing, diving, and cruising in the bay or ocean. All boats are Coast Guard equipped, with VHF radios and safety gear. Rates start at $299 for 4 hours and $499 for 8 hours. Club Nautico is open daily from 8am to 6pm (weather permitting). Other locations include the Crandon Park Marina, 4000 Crandon Blvd., Key Biscayne (tel. 305/361-9217), with the same rates and hours as the Coconut Grove location; and the Miami Beach Marina, Pier E, 300 Alton Rd., South Beach (tel. 305/673-2502), where rates start at $299 for 4 hours and $499 for 8 hours. Nautico on Miami Beach is open daily from 9am to 5pm.
A Whole New World--Every Columbus Day, Biscayne Bay becomes a veritable mob scene of boaters celebrating the discovery of another day off of work. The unofficial Columbus Day Regatta has become a tradition in which people take to the water for a day of boating, sunning, and, literally, the bare necessities, as they often strip down to their birthday suits in an eye-opening display of their appreciation for Columbus's discovery of the nude, er, new world.