And yes... variations variations variations.... I love Generative / Procedural art.
Prior to FilterForge, I used Artmatic which was a Mac program similar to Filter Forge, only comes with an extensive component library (seriously, like 400+ mathematical components.) Artmatic was a completely new, radical tool for image creation during the time of its release. Because the components were mathematical it also allowed sound synthesis based on nodes. And yes, I made music using it. Unfortunately, it simply did not have the freedom similar to what Filter Forge could do.
Oh well, I still use it when I feel like it.
Last image from this series.