I amend my previous info to agree with the water shuttle suggestion. Forget the T unless the weather is bad. I think the water shuttle costs about $8, and runs every 15-30 minutes.

Ooops, wrong again...$10.

From the water shuttle page of the Boston Harbor Hotel website:

Destinations & Fares

The Airport Water Shuttle now offers a convenient weekday stop at the United States Courthouse with free pedestrian transportation between the Courthouse and Rowes Wharf.

Convenient Destinations

Financial District
Federal Reserve Bank
One Federal Street
75/101 Federal Street
100 Federal Street
150 Federal Street
175 Federal Street
One Financial Center
225 Franklin Street
125 High Street
99 High Street
International Place
One Post Office Square
50 Rowes Wharf
75 State Street
60 State Street
28 State Street
100 Summer Street

Hotels
Boston Harbor Hotel
Harborside Hyatt
Hilton (Logan)
Hotel Meridien
Marriott Long Wharf
Seaport Hotel

Other
Children's Museum
New England Aquarium
Quincy Market
Faneuil Hall Market Place
South Station

Schedule
Monday thru Friday 6AM - 8PM, Every 15 minutes
Saturday 10AM - 8PM, Every 30 minutes
Sunday 10AM - 8PM, Every 30 minutes

Service is year round except Christmas Day, New Year's Day, 4th of July and Thanksgiving Day.

Fares
Adults $10.00 Seniors $5.00 Children under 12 FREE
Round-trip: Adult $17.00
Purchase tickets on board the Airport Water Shuttle.
Discounts available when 10 or more tickets are purchased in advance. Call 617-439-3131

[This message has been edited by Kitty Hawk (edited 10-19-2000).]