I recommend Waze. Crowd sourcing GPS navigation, with real time traffic gathering from other Waze users. You can even update the maps online if they are incorrect. And its completely free.
When I switch it on in the morning it auto plots the fastest route to work, and the same for going home in the evening. I love it.
Last edited by TravUK; 2nd June 2010 at 08:33 PM.