Mazda RX-8 H2 Hydrogen

The RX-8 uses a rotary engine, which makes it more or less unique among consumer cars. The H2 version runs on either hydrogen fuel or regular gas; a button on the dashboard swaps between the two, although you have to stop to make the switch. There are two fuel tanks: fill it up on the right side for gasoline, and on the left side for hydrogen. Max range on hydrogen is only about 60 miles, and good luck finding a hydrogen fill station anywhere near you. The H2 is currently being tested out in Japan.

Chevy Volt

The Green Car of the Year award at the show went to the Chevy Volt, largely for being the first plug-in hybrid that you can go to a dealership and buy.

The Volt is battery powered for the first 40 miles or so, with a regular gas engine that kicks in if you need to go farther. Real world testing shows that the Volt averages nearly 130 miles per gallon, although you'll do much better if you use it as a daily commuter for just 20 or 30 miles and then charge it overnight.

Fisker Karma

The Fisker Karma makes no compromises when it comes to plug-in hybrid technology. It's basically the same type of powertrain as the Chevy Volt (battery powered with a gas engine that kicks in if necessary), except that it's been massively sexified. For starters, two 200 HP electric motors together can generate more torque than a Bugatti Veyron, and when combined with the turbocharged 260 HP gas engine, the Karma goes from 0-60 in in under six seconds with a top speed of 125 mph.

Fisker Karma

On battery power alone (it charges from a wall plug), the Karma will go about 50 miles. Using the gas engine boosts that to 250 miles, and like a regular car, you can just fill it up and keep going. The roof of the Karma is one big solar panel, and in addition to helping run the AC, it can actually send power directly to the car's batteries, giving you an extra five miles a week of free driving if you live somewhere sunny. You can also buy a big set of solar panels from Fisker to charge the Karma totally off the grid.

Chevy Volt

The Volt goes on sale November 30 for about $40,000, although tax incentives will probably knock a big chunk ($7,500 or more) off of that.

Honda FCX Clarity

Honda's FCX Clarity runs on nothing but compressed hydrogen. Using a fuel cell, it turns the hydrogen into electricity to power an electric motor, and chemically pure water comes out the tail pipe as a byproduct, although they really should just run it up into the passenger compartment: “gun the engine, I'm thirsty!” The 5000 psi hydrogen tank can be filled up in just three minutes, and Honda has even figured out a way to extract hydrogen from the same natural gas that might be heating your water right now, so if you want, they'll sell you your own energy station to refuel your car at home.

Max range of the Clarity is 240 miles with a top speed of 100 mph, and if you want one, you have to live in southern California and put your name on a waiting list. The lease is $600 a month, maintenance and insurance against hydrogen explosions included.

Nissan Leaf

The Nissan Leaf is small and boring electric car, except that it has a better than average range of about 100 miles in city driving, and it's damn cheap (relative to other electric cars) at only about $33,000, before all of those tasty tax incentives. If you can find some way of hacking a 500 volt line into your house, the Leaf will recharge to 80% in just thirty minutes. Otherwise, a charge from a standard household outlet takes 20 hours (!).

You can reserve a Leaf online right now, and limited deliveries will start this December, with full production by 2012.

CODA Sedan

CODA is a small California company that's trying to produce a commercially successful electric car all by itself. Their staggeringly ordinary looking sedan (which comes in other colors besides this horrible yellow) gets up to 120 miles per charge, and recharges in about six hours (although a two hour charge gets you a solid 40 miles). A full charge during off-peak hours will run you three bucks in electricity costs.

CODA Sedan

CODA wants to stress that their batteries are thermally conditioned so that you'll get the same range in baking heat or freezing cold, unlike some other electric cars. The MSRP is $44,000, although as with the Volt, tax incentives will make the CODA Sedan substantially cheaper.

Honda Fit EV

This concept from Honda was unveiled today at the show, but it should be available on the US market in 2012 or so. The Fit EV steals the electric motor out of Honda's FCX Clarity, and gets about 70 miles per charge. Honda is pretty sure that you have no idea how to drive efficiently, so they've equipped the Fit EV with an interactive coaching system to teach you that it's not always necessary to floor it. Recharging the Fit takes about 12 hours if you plug it into your wall, but only six hours if you use Honda's sleek 240 volt charging station.

Fisker Karma

The Karma is almost, but not quite, available for purchase. The target delivery date is February 2011, and it'll set you back $87,900. That may sound like a lot, but remember, by buying one, you're helping to save the planet, and it's just a happy coincidence that you'll be going really really fast and looking badass while doing it.