It involves touch sensors, so you may want to stock up on Windex.
To paraphrase the Almond Joy commercial, sometimes you feel like a tint, sometimes you don't. In states like California, having any tint on your front windows is verboten. It's only casually enforced, but it's still illegal. In that case, something like this setup might come in handy: a Russian gent on installed two power windows in one door, and tinted one of them.
Bangladesh's car trade has virtually lurched to a standstill on account of... tinted windows. The country's government banned the importation of new and used vehicles that have smoked glass on December 12, 2005, putting serious crimp in the nation's flow of vehicles. It is estimated that the government has been losing revenue at the rate of Tk 300 million/day (or $4.5M USD for the currency-challenged) thanks to this law.