I noticed some of the union strikes are asking for a 4 day work week. I hope this can start to change the cultural mindset on this issue. Once almost everyone knows someone working 32 hours a week, people will start to question their assumptions about the 40 hour work week and will want 32 hours for themselves as well.
My company dropped down to a 4-day week with everyone getting to choose their day off - I went for Wednesday because it gives a nice mid-week break. And Monday and Friday are great for focussed work because the majority of people picked those two days.