Oh, yeah, then there's the problem with FOCUS. I have a full time job but I also teach college classes as my part time job and I have a side business but it's also teaching so I control the hours. I've been working on improving my digital photography skills (gave away my 35mm), relearning chemistry (mostly organic), and have a stack of books next to the bed about topics related to plant physiology. My wife is undergoing chemotherapy the rest of 2009 and I spend a lot of time with her both when she's undergoing treatment and when we're home. We work for the same university so we're never very far apart.
I can definitely stay focused on her and her needs but, beyond that, I may get distracted too easily and jump from one thing to another which prevents me from getting very much better at any one.