Google Maps is great for transit directions, but what if you want a gods-eye view of a city's public transportation network in motion? Try TRAVIC.
Developed by University of Freiburg grad student Patrick Brosi and geOps, TRAVIC (Transit Visualization Client) harvests public data feeds supplied by transit operators like L.A. County's Metro to visualize the location, second-by-second, of all the buses and trains in a given system. Transit vehicles appear as colored dots on a map. Click on a dot, and the software will highlight the applicable route on the map and list scheduled arrival/departure times:
Best of all, it's animated. By default, the software runs in realtime so that the dots merely crawl along the city streets, but users can speed up the animation as much as 60x. At that rate, the buses and trains zip through the city, and it's much easier to visualize frequency—and hence how well a neighborhood is saturated with transit options.
Here's the area around Union Station, a major transit hub for Los Angeles:
And here's a snapshot of Anaheim, using schedule data from the Orange County Transportation Authority:
TRAVIC actually integrates data from 72 feeds covering cities on four continents, so there's much more to explore beyond the Southland. Here's a snapshot of Manhattan: