The 1-series has been a popular staple among premium small-car buyers in Europe for some time, but it has only hit the U.S. recently. The fun-to-drive and attractive compact has just gained a new sibling in the form of the 116d, powered by an efficient four-cylinder diesel. Unfortunately it's only available in Europe. Despite the absence from American shores, it's still a technological feat to appreciate. With its 53.4 US mpg rating in the European combined cycle, the 116d is as efficient as the current Toyota Prius and next-gen Honda Insight hybrids.