TwinPower Turbo four-cylinder that's based directly off the power-plants of the i3 and i8, as noticed by Autoblog. BMW says that its plug-in hybrid tech is flexible enough that it can go into basically any of its vehicles and that the implementation can happen pretty quickly, too. If you're curious as to what it all looks like, we've embedded an official mock-up image after the break.
Considering that the 3-series is one of the least expensive ways to get into a Bimmer, let's hope that the price of a hybrid version doesn't change that too much. Oh, and if you're looking to kick petroleum out of your garage completely, there are plans for hydrogen fuel-cell models, too, but those likely won't come to fruition anytime soon.