I'm not sure if I posted this already somewhere, so I'll post again in case.
This on-line street map and journey planner is great, it uses Java, so all map interaction is on the client browser - very smooth and pleasing to the eye.
http://www.us.map24.com/
For the UK version, visit:
http://www.uk.map24.com/
So, no reason to get lost when the GPS breaks down :)