Save the planet, save on gas and burn some calories: ride a bike. I ride my single/fixed gear bike to school every day. I also try to ride it everywhere else that I can. I encourage you to do the same.
Not only do I save money and the earth, I get to dodge pedestrians.
Check out this site, they have great reflective stickers to keep you safe and trendy.
http://worldsbestbikestickers.com/
Happy Pedaling.