Working at home used to be less productive for me, but since then my office has switched to open spaces. Now every couple of minutes someone will walk by, ask what I'm doing, where I'm going to lunch, where I've been for lunch, just making idle talk. Now I either come in at 5am to avoid everyone, or just work from home. Most of the time I'm in meetings so the productivity is pretty much the same either way. On days where I don't have meetings, just having a quiet space is the most useful thing for me to get work done.