i don't own a car, so if i don't ride my bike to work, my only other realistic alternative is to ride the train (i live 15 miles away from work so walking ain't a practical option). a round-trip train fare for my commute route is $7.80. so everyday that i ride instead of taking the train, that's nearly 8 bucks that stays in my wallet. day after day week after week, month after month, year after year, that 8 bucks/day adds up. if i bike commute 200 days a year (conservative), that's $1,600 saved.

now, bike crap, new tires, tubes, chains, cassettes etc. does cost money too, but it don't come close to totaling $1,600/year.

the above doesn't even get into the fact that my bicycle-centric lifestyle has allowed me to forgo the TREMENDOUS costs of car ownership altogether!

so yes, bike commuting absolutely saves me money, but as others have mentioned, money is not my prime motivator.

99% of the reason why i commute by bike is because it's SO! DAMN! FUN!

life is meant to be lived, and bike commuting helps me live.