I have a Samsung LN40D503 and it has a USB port on the back. According to the manual, you can play music and look at photos but that's all. I have videos on a portable hard drive that I'd like to watch on my TV as well as my PC. Is that possible? The only other USB port I have is on my DirecTV HD receiver (HR21-200) which, according to my internet research, doesn't do much. I've been searching for the answer to this and can't really find anything concrete so any and all help is much appreciated!