If you belong to a club or have a prominent role in a charity, this could show that you are organized and compassionate. If you work out regularly, this will show that you are health conscious, and will take less sick days. Reading teaches you many things, so that looks good on a resume', many jobs require a lot of reading. If you Dance, this attests to how well rounded and social you are. Many skills that are used to do extra curricular activities are useful in the work environment.