Its IRL racing technology that has trickled down to us common folk. Its pretty easy with today's electronically controlled transmissions. It comes optional on automatics and manuals. With automatics, most of the shifting is done electronically anyway, so the actual shift lever is easy to eliminate and replace with paddles. In the case of manuals, its a bit different. They use automatically-engaging clutches and servo-type rails to shift the tranny for you. Its a whole different thing that I'm just beginning to understand, but if you get the chance, go test drive a new BMW M3 with the paddle shift. If it doesn't make you scream in ecstasy then you just aren't ready for it yet