What should you bring to surgery?

What are some things that people have found to be helpful to bring when you are schedule to undergo breast surgery: be it lumpectomy, mastectomy, etc.

I am curious to what would be helpful for me to bring in such a situation. I do not have surgery scheduled at this time, but trying to get a jump on it and I thought this would also be a good helpful post for others.

Please share your tips and comment on what you feel or found to be most helpful for you.

thank you in advance.