I didn't focus on my T's office surroundings at first, but twice now my T has had me go into her office before our session started, while she ran down the hall to the bathroom, so that gave me a great opportunity to just sit and take everything in! Plus, another time, my T was looking for a book for me, and I noticed that all her books were color-coded - I told her mine would've been alphabetized, and she said that would make it easier to find a book because she couldn't find the one she wanted to lend me!
There is some interesting artwork on the walls that I wonder if it came from patients. And there are kids' artwork hanging up - my T shares her office with her husband, who works with kids.