The future is now: Cars that drive themselves are taking over the road.

(FORTUNE Magazine) – SPOTTING AN OPENING in traffic, my Mercedes-Benz surges forward, then settles in at a 60-mph cruise. When we hit a patch of cars, the S-Class sedan eases off the gas, slowing to 20 mph, and finally brakes to a stop in the rush-hour snarl.

Sounds like another day, another dull commute. Except that, to borrow from the Greyhound slogan, I've been leaving the driving to Mercedes. In 60 minutes at the wheel--including traversing Manhattan's traffic-choked F.D.R. highway--my right foot never touches the gas or brakes. A flick of a lever, and my computerized co-pilot does everything but steer.

It's called adaptive cruise control. And while it sounds like something out of Minority Report, it's available today on a range of luxury models--for an extra charge. The systems scan the road with radar or lasers to maintain a safe gap between cars, while drivers can set the ideal following distance.

Car companies have more than just convenience on their radar. Mercedes claims its cruise control system could cut rear-end collisions by 75% in heavy traffic. If my model were to sense an unavoidable crash, its PreSafe system would cinch seatbelts, shift the front seat into optimal crash position, and close the windows and sunroof.

Other communicative cars are on the road as well. The Acura RL uses adaptive cruise control in its collision-mitigation braking system, which literally steps in for a daydreaming driver. When I approached another vehicle too quickly, the system flashed a dashboard BRAKE warning. If I ignored it, it tugged on my seatbelt, before ultimately braking for me. The system won't come to a full halt on its own, but it gives a pilot the critical headstart that could prevent an accident.

Some Infiniti models use an optional camera to read lane markers and chirp a warning when a driver crosses the line without signaling. The Audi Q7 sport- utility keeps an eye on its blind spots, alerting drivers if a car is lurking near its flanks. And the upcoming Lexus LS 460 sedan (due this fall) will address that bane of every driver's-ed student: It will parallel park by itself, with only a bit of brake assistance from its pilot.

In testing, the lane-warning and blind-spot detectors struck me as somewhat annoying. But more sophisticated systems, experts say, could make a big dent in the 6.2 million crashes and 43,000 fatalities each year on American roads. That's what GM is hoping to do with a new system (not yet in production) that lets cars communicate via GPS signals now used for in-car navigation. "Each vehicle is telling the other guy, "Here's where I am, here's where I'm headed, here's how fast I'm going," says Hari Haran Krishnan, a researcher at GM research and development. That could help prevent the deadly chain-reaction pileups that occur when drivers are blind to the approaching disaster.

It could also help with fuel consumption. The average commuter now spends 46 hours a year stuck in traffic, according to the Texas Transportation Institute. That gridlock wastes 2.3 billion gallons of fuel annually. With automated travel, proponents say, roadways could efficiently carry double or triple the traffic. The FCC has carved out a bandwidth specifically for vehicle communications, and a consortium of automakers is developing standards so that all car brands will speak the same language.

While such systems may be decades away, "smart intersections" are among early practical applications being studied by the Department of Transportation. Smart intersections could beam warnings to cars when another vehicle is about to blow through a red light, giving drivers time to avoid catastrophe. Ultimately the technology might slow down an errant car, making it impossible to run a red light or stop sign.

Some privacy experts worry that the technologies could be used to write tickets or track citizens. (In Minority Report, Tom Cruise's Lexus betrays him by whisking him off to the police.) But while there are certainly issues to be hashed out, in my experience that little cyborg inside my Benz drove more smoothly and sensibly than plenty of carbon-based folks I know.


Cruise control? How very '90s. These five models can make you a better driver (one even parks itself).

1 Audi Q7, $49,900

Twin radar sensors ($500) help drivers change lanes; lights flash a warning when a vehicle is lurking in your blind spots.

2 Acura RL, $49,300

The collision-mitigation braking system ($3,800) alerts driver to stop and brakes on its own if driver ignores the warning.

3 Mercedes S550, $85,400

Standard PreSafe system adjusts car when it senses a crash; distronic cruise control ($2,850) keeps pace with traffic.

4 Lexus LS 460, $60,000--$70,000 est.

Camera-and sensor-based system will handle parallel parking with only some braking help from the driver.

5 Infiniti M, FX, Q45, 37,800--$58,100

Lane-departure warning uses cameras to read markings and alerts drivers who stray from their lane.

Car prices are manufacturers' base prices.