A lot of fantastic footage has come out of the Romano Archives in the last few years. Below is another set of US gun cam footage they uploaded a couple of years ago. It is a compilation of 6 rolls of film that starts with a dogfight and progresses into ground attack maneuvers against a variety of vehicles and locomotives. This footage was all taken over Germany in March-April 1945.
Another set of previously unknown footage was uploaded by the Romano Archives last month, which can be viewed here. The above footage as well as thousands of other reels are available from the Romano Archives.