Actually, I do enjoy talking to surgery patients while they're in the pre-op holding area. Sometimes they're nervous, but they're usually pretty candid and they like talking to students, generally. A lot of times, I think that they'll talk to students just because they want to keep their minds off of the upcoming surgery.
I thought that pregnant patients were funny. (Not all med students share this opinion, though.) I had a patient who was in labor with her first baby. I was trying to encourage her and said, "You don't have a lot of time to go! You're really close! I can see the baby's head!" She then screamed out, "You can see the head?! Then pull the da*n thing out!!" Well, no...not that close....
There are other, funnier stories about surgery patients, but I can't really repeat them in a public space....