Animation Notes
The experiment was to discover if 'feedback' is possible using Gimp/MathMap/Composer. Composer is similar to using multiple effects pedals with a musical instrument.
I started with a single 3D fractal image and applied this chain of effects to it:

Composer would not let me connect a patch lead from the right hand side to any box on the left hand side. It only allows 'feed forward'.
It can do effects chains in parallel and with three mixers I could merge image streams in various ways.

I found this type of processing uses a lot of computer power. On a 4-core/4Ghx box adjusting a slider was taking a long time.
I didn't have full control over the process. I exported the frames with Gimp-Gap as an AVI and imported to Kdenlive where I finished the clip using some of the filters like mirror.
I got some ideas about improving this process. Next time I will try to make more frames and hopefully get MathMap to make them end at the beginning.
The soundtrack is from here:
https://www.youtube.com/watch?v=7avZPKlJV0Y

Awesome reminds me of 90s

Pretty cool stuff Tas, you must be smoking the good stuff...

I've done some crazy stuff too. Aviutl has a script function that can control an object to the rhythm of the music track. It makes some cool effects. Here I let it animate a tittle to the sound track of the original Dr Who. DrWho.mp4 (17.83 MB)

trandoductin - thanks for encouraging people to do music videos.
racer-x - "you must be smoking the good stuff..." It's been a long time. To be honest, I don't need it.

I like the Dr Who track. I guess the theme is owned by the BBC. I select "Creative Commons Attribution license (reuse allowed)"
as a Filter on YouTube searches.
Using Creative Commons license material means I choose that over 'Standard Youtube license' when uploading.

Tas_mania and racer-x: Fun stuff!