Rome and Teaching the New Testament (need advice)

Later in August, my family and I are taking a holiday in Rome to end our time here in Europe.  I haven’t been to Italy since I was in high school and I am very excited (my wife graciously let me choose the location of our European holiday).  One of the things I am particularly excited about is visiting those places that help illuminate the world of the New Testament, particularly Paul’s letters (and especially his letter to Rome).

Can anyone tell me the ‘must sees’ for NT archaeology (other than, of course, the colosseum and Roman forum)?  What should I be taking pictures of to use as visual aids in classes on Paul?  Basically, what would you drool over seeing in person in Rome that relates to Pauline studies?  I am specifically interested in what the normal guide books would not bring up.  But feel free to suggest anything.  Thanks!