Boats allow sailors to navigate such geographical wonders as the Northwest Passage, the Strait of Gibraltar, and their neighbor's Olympic-size birdbath. Swim with the ostriches with today's Groupon: for $149, you get a half-day pontoon-boat, runabout, or ski-boat rental from Lake Toys Boat Club, valid for five hours in the morning or afternoon on Lake Travis (up to a $299 value). This deal also comes with the option of signing up for a one-year membership, with the first month being free.

Itchy-footed landlubbers and their seafaring passengers can embark on freshwater voyages with Lake Toys Boat Club's fine fleet of Lake Toys' maritime vessels. The rental portion of this deal is valid for pontoon boats, runabouts, and ski boats, including the 2006 Sea Ray 185 Sport, an eight-passenger behemoth whose 10-speaker Hydrotunes sound system allows swimmers to doggy paddle in rhythm to ominous Gregorian chants. Before cruising past Lake Travis's catfish, largemouth bass, and Swedish kings lounging on a royal water tube, nautical novices take a training course on boat operation and lake rules, and all satisfied seafarers must refill their sea craft's gas tank before returning to port. For a monthly fee of $299, aqua lovers can embark on unlimited freshwater voyages on any of Lake Toys Boat Club's vessels.