The brakes on BMW's new 3-Series feature a host of life-saving tricks packed for the first time into one vehicle. They anticipate an emergency stop and cinch the pads closer to the rotors, so they engage faster. And because they resist fading during long descents, you can stop quickly at the bottom. They also squeeze the calipers intermittently in the rain to keep the pads and rotors dry and, when stopped on hills, hold the car while you move to the accelerator.

Michelin aims to eliminate flats and blowouts with its remarkable Tweel concept, an airless one-piece wheel-and-tire combo that could soon enter production. The Tweel's hub connects to polyurethane spokes that assume the shock-absorbing role of a traditional tire's sidewall. The spokes are bonded to a reinforced rubber tread band that can be as specialized as today's tires. By varying the thickness and size of the spokes, Michelin can generate a wide array of ride and handling qualities.

Dropping the top on the new Volvo C70 doesn't mean sacrificing safety. Side-curtain airbags, previously found only in fixed-roof vehicles, typically deploy downward from the roof. The C70, available this spring, shoots them upward from the doors, using vertically oriented air chambers like inflatable beams, so it doesn't matter if the roof is up or down. And they stay inflated longer, keeping your head and limbs inside the car during a rollover.

Now available in Europe in the sporty Golf GT, Volkswagen's Twincharger system consists of a highly economical 1.4-liter direct-injection four-cylinder engine equipped with both a supercharger and a turbocharger. The supercharger, belt-driven off the crankshaft, compensates for the engine's small displacement by forcing air into the cylinders at low revs to bolster torque. As the tachometer climbs, an exhaust-gas-driven turbocharger further boosts the horsepower. The GT hits 62 mph in 7.9 seconds and goes on to 136 mph, while returning an impressive average of 39 mpg.

With twin 5.7-liter Hemi V8 engines and a super-stiff carbon-fiber body, the Jeep Hurricane concept truck is the boldest, most fearsome rock crawler ever built. But the real achievement lies underneath. A central transfer case called the T-Box receives the opposing engines' driveshafts and apportions a combined 700 horsepower and 750 pound-feet of torque to all four independently sprung wheels.

For its new Civic Hybrid, Honda engineered a gasoline-electric powerplant that's more powerful (110 horsepower, up from 93) and fuel-efficient (50 mpg city/highway). To increase the torque and horsepower from the 2.8-inch-thick electric motor, engineers cleverly swapped the round wire in the motor's armature for a flat one. That switch let them cram more wire in, increasing the power density. During deceleration, when the electric motor becomes a battery-charging generator, the variable-valve-timing system seals the gas engine's cylinders.

Converting an engine to burn ethanol is a relatively simple matter of replacing some hoses and seals at the factory, but the Saab BioPower engine is the first to use the corn-based gas to actually enhance performance. Available in Sweden in the 9-5 sedan and wagonand possibly later in 9-3 modelsit generates 148 horsepower on pure gasoline, but when it sniffs ethanol, it cranks up the turbocharger's boost pressure (ethanol can handle higher pressure better than gas) to lift output to 184 horsepower. How's that for an eco-friendly incentive?