The idea behind torque vectoring is to spin the outside tire slightly faster through a corner to point the car into a turn. Traditionally, this was accomplished with a complicated mechanical differential, which is what's used in the BMW X6, the Ferrari 458, and Acuras equipped with Super Handling AWD. While torque vectoring is awesome and results in physics-defying handling, it's still relegated mostly to pricey luxury cars. That's changing, thanks to a simple formula tweak: Instead of speeding up the outside wheel, it now slows down the inside wheel. And that doesn't require anything fancier than brakes and software. Voila! Torque vectoring is cheap enough to show up in the 2013 Nissan Altima, where it's called Active Understeer Control. What once required genius mechanical engineering is now handled by a few lines of code.