Pegontheroad, on our first visit to Rome, seeing the SPQR on the manhole covers was one of our favourite moments too!

Taffy, if you're an animal lover, you might enjoy the Torre Argentina cat sanctuary:

http://www.romancats.de/romancats/index_eng.php

We are not much of the museum types either but as most of the people have responded earlier you can just walk, walk, and walk around and come across so many interesting buildings and fountains and piazzas. After we were tired of walking around for a few days we took a day-trip to Capri and believe me that was one memorable trip - we got to sit in the bus for a while (not walk all the time) and saw some of the most beautiful sights. The blue grotto (spel?) is THE MOST AMAZING thing.