road rage responses range from a flip of the bird to some gentle highway drag racing. For an enterprising hacker by the name of Gagandeep Singh, however, those on-road hijinks have given way to a more eloquent, albeit LED-lit resolution. Conceived as means of informing errant drivers of their transportation follies, Singh rigged up a 40 x 16 LED matrix display and affixed it to his car's rear window. Using an AT89C51 micro-controller, hard-coded messages and animations are then fed to the 2cm x 2cm grid, much to the chagrin of reprimanded drivers following close behind. Eventually, this helpful hack'll hookup with a mobile phone over Bluetooth, delivering real-time updates (and insults?) to the display. Until then, you'll just have to make due with Singh's step-by-step DIY at the source. Jump past the break for a scrolling view of this corrective driving tech.