Couldn't you work 6 hours "for the man", and then work on a project of your own choosing, for whatever reason you wanted? (a side project, the next unicorn, some spare cash, something OSS, something for charity, or just because)
In Norway at least, it's true that lots of people finish work relatively early - but only because they start work really early (6-7am)!
I had searched for the sarcasm in previous comments in our thread to no avail!