That all-encompassing bastion of internet data, Google, has launched a new service in their labs for transit maps and routing information. It shows a map from your starting location to your ending location along with how to walk to the nearest transit station. It gives you the next few departure times and the duration. And, ta-da!, it gives you the cost of transit vs driving. Pretty neat, but it only covers the Portland, Oregon area for now.
Having lived in Portland, I took some time to play with it. It seemed to have trouble identifying common landmarks like Lewis and Clark College, so I had to find the address myself and plug it in. It's neat when it finds the location, but it's finicky.
I'm having trouble with the page display in Camino 1.0b1, so you may also have problems with Mozilla and Firefox. There are no vertical scrollbars and using the arrow keys moves the map only. I'll send something to Google about it when I get some more time this evening.
Looks like something with a lot of potential when they add some more cities and work out the bugs. If you want to check it out, go to http://www.google.com/transit.