Toyota patents augmented-reality windshield
Head-up displays as they currently exist push static images from the dashboard to your windshield using reflections. Toyota's system acts in that same way, but instead of just displaying data pulled from the instrument display, it takes readings from speed and steering-angle sensors to change the output in real time.
Perhaps its main feature, or at least the feature most talked up in the patent itself, is the ability to display the vehicle's lane positioning in real time. As you move, you'll have an image that shows you where the edges of your car lie within the lane. Now, you'll never need to wonder exactly where your vehicle's extremes are -- you'll be able to see them right in front of you.
If this ever makes it to production (a good deal of automotive-patent tech tends to disappear into the ether), I'll finally understand why that damned chime keeps going off.
See the original post here: http://www.cnet.com/roadshow/news/toyota-patents-trick-augmented-reality-windshield/