At the Noank Shipyard in Groton, an antenna moored to a fuel shack just a few feet from the choppy waters of Long Island Sound allows customers to check their e-mail and access work from their computers without ever coming ashore.
"If you hang out on a boat Saturday and Sunday, it's because you work Monday to Friday," said Russell Schmidt, co-owner of Beacon WiFi, a wireless provider based in Wilton.
His business takes in marinas in wealthy enclaves such as Sag Harbor on the eastern end of Long Island, Block Island, R.I., and Charleston, S.C.
Beacon and other companies are working to fill in blank spots where WiFi doesn't reach between marinas up and down America's coastlines.
He is now harbor master at a marina in North Fort Myers, Fla., and said the advent of wireless technology has made his life easier.
"You could sit at the Clam Shack with a cup of chowder and figure out what the stock market is doing," said Kathleen Burns, general manager of the Groton shipyard.
ICOA is beginning to establish a presence at marinas in Virginia and Rhode Island, and provides WiFi to 55 marinas, said John K. Balbach, vice president of corporate development at ICOA.
An increase in the number of devices equipped for Wifi -- personal data assistants, phones that switch between cellular and WiFi, hand-held gaming devices and digital cameras -- are helping to spur WiFi business, Balbach said.
At marinas, "wireless is a perfect solution" because marina facilities such as restaurants and yacht clubs, along with boaters, can pick up signals, he said.
Kevin Keating, general manager of BroadbandXpress LLC, which provides WiFi to marinas in Washington state and British Columbia in Canada, said access to the Internet and e-mail provides important information such as up-to-date weather forecasts.