Take a clip of a sports event, baseball, football, basketball etc.  Take the commentary from a different sport and add that commentary over the original video.  Try and get the audio to match up so it makes at least a little sense.  Make it comical, have some fun with it!  From experience, the hardest part is finding a video clip and audio clip and getting them to match up.  After that, you’re golden! An example of this is from SNL below…