Boston has undergone quite the transformation since the "Big Dig" was completed. The giant green Expressway Bridge that once cut through the city, has been replaced by the walkable, enjoyable, pedestrian pathway that was built in its place-the Rose Kennedy Greenway. And with everyone going "green" Boston is not missing a beat.
Hubway is just one way that Boston has jumped on the green bandwagon. Providing bike rentals at various locations throughout the city, these Zipcar style bike rentals allow renters the chance to take a ride and return the bikes to any Hubway location around Boston. Hubway riders get a discount if they join and membership options range from one day, 3 days or full-year. There is one glitch: costs can quickly soar. A twenty nine minute ride is included in the membership fee so as long as you return the bike to a Hubway station before you reach thirty, you add zero dollars to your membership cost. Meaning, throughout the term of your membership you can theoretically take as many twenty nine minute rides as you'd like, but you must stop at a Hubway station and re-check out a bike before you reach thirty. After that, expect to pay a pretty penny for your time on a Hubway bike. After three hours of uninterrupted Hubway riding you'd be better off renting from a regular bike rental company.
The upside to Hubway, though, is that it's a simple way to skip the cab, shorten a walk, or just enjoy a little bit of biking throughout Boston. 
Hubway Bikes — Photo courtesy of Hubway