Is there a good application to edit .mov or .mp4 files? Good as in where you have the option to copy just the video or just the sound and paste it in another .mov/.mp4 file? I've looked at QuickTime (Paid version.) and iMovie and it looks like they don't have these options. If one of these programs do allow this, there a guide some where on how to do it that this n00bie can use?!