We reported about the GPS HUD (Heads-up Display) from GlobalTop a couple of weeks ago and it really sounded promising.

The GlobalTop HD100 GPS navigation device displays your speed and other navigational info, like direction, onto your car's windscreen, a feature only known from premium limousines.

The good news, it works. The bad news it looks awful. I do not want to see retro red LED segment digits on my windshield. It makes the whole gadget looks like homemade. See below a how the BMW 6-series Heads-up display looks like.
GlobalTop needs to change the unit into using a full graphical display to be able to show a somewhat stylish and state-of-the-art display to succeed with this in principal great product idea.
The photo above is courtesy of Engadget. They took some more photos of the GlobalTop HD100 prototype at the CeBit 2007. The price is supposed to be only $100. Still, I think the display needs work.