The Roma Pass by nyonnetti
One of the best deals in Rome is the "Roma Pass." It is a 20 Euro investment but well worth it if you plan to be in Rome at least 3 days. It covers admission to two museum/sights and unlimited metro/bus transportation for 3 days. We used ours on the Coliseum (11 Euro) and the Borghese Gallery (13 Euro). Then, with the number of times we used the metro and bus, we saved at least 10 Euro by getting the card. We bought our Roma Pass at the Palatine Hill ticket booth, but they are sold in Tobacco shops and other various locations as well.