"If you are really passionate about it, you will feel depressed or even physically ill if you are prevented from working on it. This level of motivation will give you a fighting chance of actually getting something done, despite the other demands of life."
In the past, I have written about passion, or perhaps how I don't seem to experience it in the way other people in the computer industry do. However, I can honestly say that I feel depressed when I do not have the opportunity to do network software projects. I always have. In fact, I have the distinct feelings of separation and loss. So while I may not show the exuberance of people who are giddily excited about what they do in software, I definitely experience being denied the opportunity to do work I enjoy in a way that can be related to passion.