I am in need of seemlessly looping background video for church-use and so have learned how to use Adobe AfterEffects to create one for myself. I used the Fractal Noise preset and tweaked it until it worked. The original is 6 seconds long and it is looped about 5 times in the video here.
We'll be using this as a background to song lyrics in ProPresenter. Eventually I'd like to make some backgrounds tailored to the songs that we frequently use....have the title or something right on there.