I'm about 50/50 with how much time I spend working from home and working from the office.  Boss only requires I'm in the office when he is or when we have meetings (or when I need to use a fax machine, the only thing I don't have at home).

At the office, I'm fairly secluded in the very back next to my boss's office so it's quiet. I do have a cubicle near me with a copier, fax machine, supply area and a mini refrigerator (which I just added). My work area has two full walls and one half wall, the space in front of me is open. It's perfect, enough to give me my own private space but open enough to let me feel like a part of things when people do wander all the way back to my desk.

To top it off, we have our own private entrance.  I think it used to be an emergency exit but there's no alarm on the door so it's great when I want to step outside and enjoy the beautiful California sun.