Free from aerodynamics-inhibiting dirt and grime, clean cars can focus on what they were originally built to do––dominate in the 200-meter butterfly. Smooth your vehicle's surface with today's Groupon: for $13, you get a Superior Diamond interior and exterior wash at Diamond Finish Car Wash in Mission (up to a $25.99 value).

The sultans of suds at Diamond Finish cosset cars from wheel to top, cleaning, polishing, vacuuming, and drying chariots using a roster of environmentally friendly products. The 15-minute service commences with a speedy vacuuming of the interior and a wipe-down of the dash and console, banishing potato-chip crumbs to Elba where they can plot their return to power. Windows sparkle after an inside and outside scrubfest, and wheels roll happily through a cleaning and brightening. The wash-wizards perform the automobile equivalent of washing behind one's ears with an underbody cleaning, and tire dressing readies wheels for driving on black-tie blacktop. Mats undergo a machine washing, and a white-wall scrub readies jalopies for a clear-coat protectant and triple polish. Minivans, SUVs, and tricycles designed for elephants are subject to an additional fee ($1–$2).

Though Diamond Finish Car Wash sometimes features a discounted price online, this Groupon still offers the best deal available.