Most American cars just sit around doing nothing for 22 hours a day. A few brainy people in San Francisco thought there should be a way to get them moving, and came up with Getaround, a peer-to-peer car rental service. Think of it as WeCar between people.

The venture is heavily dependent on social media and smartphone technology (owners and renters must download the company's app). It's also very practical: Berkshire Hathaway provides liability, collision, and comprehensive coverage for the duration of each rental. And of course, it provides a bit of spare cash to car owners.

For more, click here.