When I was an undergrad i observed a number of TKAs, THAs, scopes, saw a lap-assisted vaginal hysterectomy, nose job, T&A.. It was a pretty cool experience. It was through a program my university had set up with a local hospital, which is how i got to see such a wide range of things, I didn't know the surgeons i'd be shadowing any given day, and they likely didn't even know they'd HAVE a shadow 🙂 Previous posters are right, you'll likely be situated outside of the sterile field standing on tiptoes to see what's going on, so if you have a choice you either want big open procedures like joints, or scoped procedures so you can watch the tv. the exception for me for staying far away was a.) on the facial stuff i saw, they didn't care too much if i got close. there's no such thing as a sterile oropharynx ;-) Also I'd had several intelligent conversations with the same orthopod about the instrumentation he was installing and how the body would react in different situations (I'm an engineer), and at one point i guess he decided i'd earned a peak so he had the scrub nurse get me gowned and gloved and let me come examine the hip he had put in this lady's hip and see the anatomy and all. Not the same as being scrubbed in at all, and i didn't touch ANYTHING, and it was only for like a minute then I was banished again, but still pretty cool.
I also did some shadowing in a peds office where 3rd year rotations are done, which was cool as I was kinda accepted into the fold. You can definitely see more and ask more questions in that environment than in the OR.
My experience was that the pods were nice but very busy, general surgeon never spoke to me, the ent guy I shadowed was pretty nice and laid back, the anesthesiologists were ALL laid back 🙂