Drive the streets of San Fran
I stumbled across this little gem today. It's a technology preview app using AJAX and Virtual Earth that allows you to navigate the streets of San Fran and Seattle as if you were there yourself. It's pretty neat, and I guess it would be useful before setting out on a trip, so that you could familiarise yourself with the route and any landmarks.
Have a look: https://preview.local.live.com/