Virtual Cable takes your GPS and raises you a heads-up display
This is really cool! Check out this post from Autoblog:
Filed under: Safety, TechTwo things plague GPS users: being forced to deal with dubious direction vocalizations and the amount of time spent looking at the screen when you should be paying attention to the road. MVS is developing a solution and it's likely the most revolutionary concept to date.
The system is comprised of a series of mirrors that project a three- dimensional line onto the windshield giving drivers a heads-up display of their intended path of travel.
(from: Virtual Cable takes your GPS and raises you a heads-up display)
The other really cool idea I have seen for making it easier to follow a route computed by the GPS is to project a virtual car on your windscreen which you are supposed to just follow. This was from an Engadget article about a Microsoft Patent.