Everyone on my team works remote one day a week at their choosing.
We just have one Wednesday guys who swears by it, but im a Monday remoter and it's my jam. To each his own.
Ryan mentioned employee retention and even though I work from home during my non office day, it's definitely a huge factor when other opportunities come knocking at my door.
Not yet but do plan to in future when I have more control over my paycheck. In theory it sounds as if it will cure the productivity loss coming from Monday morning blues and early Friday - would be interesting to test it out.