I find that it goes in phases, you can't sustain it all the time. I have fallow periods when I just get my head down at work and relax afterwards. Then I get

I find that it goes in phases, you can't sustain it all the time. I have fallow periods when I just get my head down at work and relax afterwards. Then I get some consuming interest and I find I have the energy to work on it outside work for a few months or a year.