More than anything else I remember the teachers personally. Most were a pleasure to be around. There is nothing better than interacting with people directly and having everyone be on a personable level. I really enjoyed talking with professors, going to their homes, going into Brat for drinks, etc. Looking back I think the most important thing to realize is that you are never out of school.
Life is always about change and learning something new.
It never ceases to amaze me when I meet important people in the computer industry and realze they are human too and that they are also clueless at times. Marlboro helps teach that. Same thing with the students. It was great to interact with all the students in different fields and get their viewpoint on problems. The experience has definitely helped me to become a better software engineer.