It's a radical concept, but if you want to eat waaaaay more food than usual, lose weight, and get more fit--drive less. Walk your happy hiney to the store, the post office, your friend's house, wherever. You will save lots of gas money, which means you're keeping gas out of the environment, and your butt will be look awesome.
I have a theory that walking is also good for meditation. When you walk, you aren't (hopefully) distracted by music or texting or what have you. You're in tune with the rhythm of your feet, and that pulls you in to the rhythm of your soul. It's good for you, keeps you from making yourself busy all the time in an effort to avoid whatever it is in your head that you may not want to contemplate.
And, walking could save the planet.