Love the idea of sparks from your boots! but your right, land you in some hot water.
On the real tho... I generally throw a hand behind me with a forceful "YO BACK-UP" motion, and they generally back the f$ck up. If that doesn't work, I move over so they can pass, and then I scoot back behind them, at a safe distance. Flooring it isn't generally an option in rush hour traffic on i66.