Let's say you'd like to work on some stuff of your own that you like, that makes you happy and most likely that will make your resume look good (although it won't probably pay the bills in the short term). Let's also say that you have a job that takes up a lot (like, really a lot) of your waking time -- and yes, you need to sleep quite some time in order to be fully functioning.
What would you do? Keep your job and hope for some more time to work on your weekend projects or make the leap and leave the workplace, possibly getting some money working as a contractor here and there?