I recently asked to take Friday off and Thursday to work from home. Plan to start next month. I would like to push it to 3 days, but nevertheless its a great start. Doesn't make sense to waste your life in front of a computer...
By the end of the day I had a part time offer and a raise. The market is in our favour at least for now.
Interestingly, after 6 months I dialed back to 4 days a week. I felt too disconnected with the projects and the people, and procrastinated too much in the 4-day weekend. I found 4 days to be my personal sweet point.