When Prada created its latest limited edition timepiece, the global behemoth could have rested on some pretty reliable design laurels, equipping it with little more in the way of innovation than a perpetual calendar or chronograph. But Miuccia Prada, who no doubt noticed that solar panels are popping up on everything from parking meters to private homes, asked her team to do their small part for the planet. The face of the solar watch is carved out of a photoelectric cell to keep the quartz movement humming on just a touch of golden rays, requiring direct sunlight as rarely as once a month. And, ensuring that each of the 1,000 individually numbered tickers is every bit as accurate as it is painstakingly crafted, the watch sports a radio receiver to tune in to the exact time. It will even spring ahead as you cross time zones between London and Paris. The artful one-two technological punch is finely accented by the gun-barrel-gray titanium case and the choice of either a dark-brown antiquated or black Saffiano leather strap. The downside: The watch is currently available only in Europe, and the radio receiver won't function in the U.S., even if the North American sun keeps it powered up. Still, for those who regularly cross the pond, Prada has managed to alchemize its high-design aesthetic into one high-tech timepiece.