Look at my new shirt: INFINITY miles per gallon, get it? Hehe.
Here are a couple of links worth checking out. If you are contemplating biking to work, this site answers a lot of questions. If you live too far from your workplace, this site will give you a list of bikeable locations in a 2-mile radius from your house (here's the YouTube video.)
If you are still wary, then you definitely need to click here: this calculator will tell you how much money you will save, how many calories you will burn, and how many pounds of toxic emissions you can save by a single bike trip. My round-trip distance to work is 7.5 miles: So if I were to bike to work just one day a week, I'd save $161.72, burn 14,040 calories, and prevent 379 pounds of emissions from entering the atmosphere. (There's also a calculator here: this one said I will only save about $60 - it's probably more accurate.)
If you are way into keeping stats, try out BikeJournal - here you can enter your distance, time, and other info on each ride, and it will all be added up and averaged for you. You can set up a goal, say ride 1,000 miles a year, and a cute little ticker will tell you how far along you are. If you are on Ravelry, there is a biking group called Two-Wheeled Knitters that is a lot of fun to follow.
