Comedy Central's "South Park" once dedicated an entire episode to mocking apocalyptic "smug clouds" created by Prius people. Well, those people will have more fuel for their smugness with the all-new model that boasts 51/48 mpg city/highway—enabled by a tiny four-cylinder engine, batteries, and active aerodynamics. Reflecting Prius' iconic high-hatch shape, styling is more aggressive, with LEDs up front and lit batwings at the back. A simplified interior adds a new color heads-up display, passenger-recognizing A/C that automatically adjusts airflow, dynamic cruise control, and all the latest collision avoidance systems. It may make Prius people even smugger.