The purpose of this page is simply to introduce the topic. The available range of filters, special effects software, and skills, is far beyond anything I can cover, especially on a single web page.
While the original "white on black" physiograms are interesting, and can be attractive, they are also useful source material to be turned into abstract images of many kinds.
Most, perhaps all, photo-editing packages have filters that transform images. Here are a few of the many on this website that combine different filters from the Photoshop filter gallery:
I mainly use Photoshop, but I also have some other packages, typically free with something else I bought. Here is the result of an hour or two with procreate's Painter Classic package. (I am not familiar with all the things this package can do). However, because I am more familiar with Photoshop, I later converted these concepts into Photoshop versions, mainly using the "gradient tool", plus a "gradient map" for the backgrounds:
Photoshop's "layer styles" provide some interesting effects, including "satin" styles and drop shadows. Here are a couple, both of them from the original on the left:
There are many more possibilities. Several more are shown in the "processed physiogram" gallery.
An obvious technique is to use Java applets. I use some written by other people. Have a look at these pages:
Tell me what you have. If it adds value, I will link to it. Let's push this topic forward, for the sake of future photographers!