I'll bet you and your significant other always sleep on the same side of the bed. Doesn't matter if you go on holiday, move house, stay over at a friend's, whatever. You each have your side.
It's the same for creative teams. Right now - because our new company installed my partner's computer on my desk and vice versa - I'm on the 'wrong' side of the bed. And it feels very weird.
Other things that feel weird:
It's Lotus Notes here not Outlook Express. Mac not PC (where's the delete key?) People putting meetings in my electronic diary instead of just popping round. Walking out of the office and being in the middle of Soho. An agency that has a feeling of buzz. Different carpet. Different people. Walls. Everything.
Amazing how institutionalised one becomes (I was at the last place for 7 years). Or perhaps no one else can relate to that, because no one stays anywhere for as long as 7 years nowadays. Or can it happen even in 1 year or 2 years?