Of late, Mountain View residents may have mistakenly identified a spinning-camera-crowned Prius or Audi TT as a Google Street View car.

Anyone who waved at one of these vehicles in the hopes of one day appearing on the web, shouldn't be too disappointed, however. While those who gesticulated wildly at one of these vehicles haven't secured a spot on the Google Maps feature, they can rest assured that they were waving at what could be the wave of the future -- self-driving cars.

That rapidly spinning camera, a laser range finder and radar are all being used to give a computer inside the car all the information it needs to pilot itself through a variety of traffic conditions, according to an official Google blog.

The cars have logged more than 140,000 miles, driven across the Golden Gate Bridge, wound down the crooked Lombard Street and even navigated from Mountain View to Santa Monica, according to the blog.

Two engineers sit in the driver's and passenger's seat at all times when these cars are on the road, according to the blog, and taking control is as easy as turning off other cars' cruise control features.

According to an article in the New York Times, the cars are still years away from being ready to go to market, but those involved with the project have said they are very excited about the potential of these systems for increasing road safety and saving energy.