1. Wood Toy Car. Plastics are apart of almost every toy but there are a few wood car toys out there like cars from Automoblox and Playsam.
2. Fuel Cell Toy Car. There are several very good fuel cell toy cars but the best looking ones are the H-Racer and Hydrocar.
3. Solar Powered Toy Car. There are lots of cool, solar toy cars but I really like tiny, solar cars like the Owi.
4. Wind Powered Toy Car. This is the only wind powered kit I know of that comes with a toy car but the Windlab Junior is also a very good wind turbine toy.
5. Wind Up Toy Car. There are a few good rubber band cars but nothing beats the old, metal key, wind 'em ups.
6. Flex Fuel Toy Car. I am cheating a little here because diecasts are not exactly toys or green but you can find almost any car in diecast form usually with fine details like working doors.
7. Pixar Cars Fillmore Toy Car. The character Fillmore in the Pixar movie Cars is a VW Bus that liked to burn alternative fuels.
8. Gravity Powered Toy Car. Good ol' gravity powers these races cars in this double spiral race track toy from Fisher-Price.
9. Air Powered Toy Car. Not quite at the level of complexity of the Air Car but balloon toy cars are very popular and fun.
10. Fair Trade Toy Car. That smiling, little toy car may not look like much but a lot of thought went into it; it's Fair Trade, made with sustainably-harvested wood, vegetable dyes and non-toxic coating.