Thin red line
I don't own a SatNav, don't worry I'm not one of those wankers who sneers "d'uh just learn to read a map douchebag!" A gadget that's car related? It's bound to be *ahem* right up my street, instead I'm religiously opposed to them as a practicing skinflint.
Not being experienced in using the little blighters I'm not sure what their performance is like but I am taken by a product being developed by US company Making Virtual Solid called Virtual Cable. It displays a red route line on the driver’s windscreen just like a fighter pilot's HUD with no need to take your eyes off the road.
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Users input their required destination through their existing satnav and Virtual Cable then uses the routeplan the gadget comes up with to display the red line, which is achieved using a combination of lasers and mirrors hidden behind the car’s dashboard.
That's right, it uses frikkin' laser beams, and there's nowt cooler than that.