For many years, the Toyota Prius was considered a "niche" vehicle, appealing only to environmentalists. Indeed, the same could be said of all hybrids, despite greater acceptance in recent years. However, now the Prius is the third best-selling car model in the world, according to Automotive News.

Some might see the Prius' rise up the sales charts as a technicality. Toyota recently introduced several new versions of the Prius, including a plug-in, wagon and subcompact. Together, these are known as the "Prius family," but Toyota counts them all as different versions of the same model for sales data. That allows the company to claim 247,230 sales for the most recent quarter, behind only the company's Corolla and the Ford Focus as top sellers around the globe.

Technicalities aside, the Prius' jump to become a mainstream hit is impressive. The Prius C subcompact has been turning heads worldwide, but especially in Japan, where it's known as the Aqua. Incentives by Toyota and great fuel economy have helped this small car become one of the most popular models in the country, and Prius sales have been up worldwide due to high gas prices.

Drivers looking to improve their fuel economy don't necessarily have to go buy a Prius. Properly inflating tires and getting a car tune up can help improve MPGs at a more affordable price.