Symbols effect
Drop in an image or a video and it gets cut into four brightness bands. Each band is stamped with a tiny symbol, tinted with its own colour, so the picture is rebuilt out of little marks. It all runs on the GPU, so video plays through it live.
The symbols, the colours and where the bands split are yours to change. When it looks right you can save a still as a PNG or record the whole thing as a video.
It runs entirely in the browser, nothing gets uploaded, and you can grab the code below and drop the renderer into your own project.