Lesson #1 - Don't Record Video in Portrait Mode
When recording video on the iPhone (and I'm guessing on any phone or small form-factor video camera for that matter), use landscape mode (with the big side going left to right). Now I usually shoot photos in portrait mode and it's real easy to flip the orientation of a photo by right-clicking on the photo in Windows Explorer and choosing Rotate Clockwise. Well with videos--guess what--this isn't so easy. Plus if you plan on watching the video on a television, portrait videos will look lousy, even after flipping it.
Lesson #2 -- How to Flip a Video
So if you happen to record a video the wrong way (see lesson #1), you will need to flip it unless you want to rotate your head sideways while watching it. Now you'd think this was pretty simple, but it's not. I guess the video editor needs to literally flip every frame of the video and then you need to re-save the flipped video.I tried flipping the video using 4 different pieces of software: