Photos: Hybrids that give back to the grid

The battery meter isn't ready to sit alongside the speedometer and tachometer just yet, but manufacturers are starting to show more interest in the concept of a plug-in hybrid, said Felix Kramer, founder of CalCars. Still, it's going to take quite a bit of investment before the technology is ready for inclusion in mass-market vehicles.

Photo by Tom Krazit/CNET News.com