Honda Civic - Gas, Hybrid and CNG - It's Your Choice
American Honda Motor Company may be the first automaker to offer a car line - the civic - in standard gasoline, Hybrid and Compressed Natural Gas (CNG) 
"The Environmental Protection Agency (EPA) has recognized the natural-gas Civic GX as the cleanest internal-combustion vehicle on Earth. Plus, the California Air Resources Board gave the GX an AT-PZEV emissions rating, which means it's still the "Cleanest on Earth."
"Civic GX owners can purchase their own home-refueling appliance called Phill, which installs easily to a home gas line. With Phill, GX owners fill up when they come home, instead of having to go to a gas station."
The gasoline and Hybrid version are offered pretty much nation-wide. The CNG version is only available at select dealers in California and New York.
Via: American Honda Motor Company Link-CNG Link-Honda