I'm quite surprised the Bolsheviks didn't introduce a revoltionary calendar after the October Revolution along the lines of the french one
They did and it was a complete mess. 5 day weeks with one designated day off based on the "color" of the day, designed to have 80% of the workforce at work at every possible moment. 72 weeks, each week being 5 days, and the last 4 days were Soviet holidays that "didn't count" towards the week they took place in. Had the same year as the Gregorian but was still fairly radical.
http://en.wikipedia.org/wiki/Soviet_calendar