When I worked at Cisco Systems circa 2003/4 myself and the other data warehouse developers came into the office once every two weeks, the rest of the time was at home. I wasn't directly employed by them (I worked for a small consultancy) but the same rules applied for permies on the same team.

Right now I contract for a large investment bank and the dev team are rarely all in the office any given day. This is due to a simple desk space shortage - I work from home 2days every week.