I’ve grown tired of these work life balance discussions, I agree a balance must be struck, however the nature of information technology is about understanding, not knowledge, what is the truth, what is the problem is all i ask.  For best results, read a book, or play a game, or write some code, even do your art or music for a couple hours before you go to sleep, as you sleep your brain will repair itself where you were stressing it by performing your activity, and your subconscious will begin to sort out the stimuli you were exposing yourself to, finally in your sleep you may find what was bother you, or trying to understand, if you wake early, your memory may be intact long enough to recall it, and therefore wake with the answers you were looking for, ie solving a problem, and something new will be added to the world knowlege base. therefore early to bed, early to rise, makes a man happy healthy wealthy and wise.  still true.  Another saying, I see so far because I stand on the shoulder of giants. JOsH