We all pluck from the same ether. It's not that weird for all of us humans to have extremely similar ideas. Which is why I think US Copyright laws need to be reformed badly.
i duno - depends on the work you do I'd say. I work one job 3 days a week, and another job two days a week and it works great for me. One of my jobs is pretty easy, the other is hard. So one is kind of a vacation from the other. Also the best part about having two jobs is - if one job hassles you, you can say "ok ill just get hours from the other one". So neither job can really hassle you :)