Still images from 16 video cameras focused on Interstates 395, 495 and 66 in Virginia are available on a site maintained by Erol's, a local Internet service provider, and Pacific Sierra Research Corp. The cameras are operated by the Virginia Department of Transportation and are trained at some of the nastiest patches of roadway, including the Woodrow Wilson and 14th Street bridges, as well as the intersections of I-66 and I-395 with the Capital Beltway.

Erol's plans to add nearly 30 more locations in coming months and is considering providing other information compiled by VDOT, including average traffic speed, congestion predictions and full-motion video clips from the cameras.

Like most Web sites, the information isn't always available or up to date. On a recent morning, some of the images from Erol's were more than three hours old. And the images can be difficult to see at sunrise and sunset.

In Maryland, the Montgomery County Department of Public Works offers on-line images from three of its cameras on Routes 355 and 118.

Other sites frequented by local drivers are the national "Speedtrap" and police car registries, both of which include sections on Maryland and Virginia. The first registry lists, in no geographical order, locations where police departments have most commonly been spotted apprehending motorists for speeding, based on e-mail notes from local drivers. The "Cop Car Registry" describes in detail the types of patrol cars, including unmarked ones, driven by officers in various area departments.

The region's two commuter rail systems, MARC and Virginia Railway Express, have sites listing schedules, fare information and services they provide. The VRE site even has a quiz to test riders' knowledge of the system.

Metro has no Web site, but maps of the subway system are available from a host of other sites. The most helpful Metro-related resource is a "subway navigator" designed by a man in France that allows you to find out your route and travel time after entering your departure and arrival stations.

The Metropolican Washington Airports Authority recently launched a Web page for Dulles and National airports that has terminal maps, transportation information, links to airlines' home pages and information about construction projects. Baltimore-Washington International Airport has its own professional-looking site with a detailed map, links to airlines and, like Dulles and National, a connection to Alamo car rental's on-line reservation system.

The Virginia and Maryland departments of transportation also have easy-to-use sites. In addition to standard information about road projects and driver safety, Virginia's allows users to e-mail local transportation planners and to view a map of highway construction areas statewide.

Staff writer Dan Beyers contributed to this report

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