Americans often speak of the $100 hamburger, the food of choice at some airport café a Cessna hour away from one’s home base. The trip to eat and return often accounts for that sum, with avgas stretching toward $6.00 per gallon. Imagine, then, making a coast-to-coast trip across one’s native land, surveying a dazzling array of scenic delights and partaking of French cuisine along the way – all for not quite that amount. Europe abounds in small, turbocharged Diesel automobiles, sometimes zippy little things that exhibit excellent fuel economy. Many of these cars strive for the “3-liter” designation – the ability to drive 100 kilometers (62 miles) on three liters of fuel (78.4 miles per gallon) and the European Union is pushing …