Having hobbies and interests outside of work is a vital part of maintaining a healthy work/life balance. However, carefully consider what you choose to share. Choosing hobbies that align with your career pursuits can advertise you as a career focussed individual who is motivated by what they do. Yet sharing that you are the lead singer in a band that performs every night of the week and has a raging back stage party after every show could raise a red flag on where your priorities lie and could present a career/hobby conflict. Also, try to excite memorable conversation when answering this question. The more professionally memorable you are, the more likely you'll be invited back for another interview.