Note: Always ensure you download such legacy content from trustworthy sources to avoid malware, as many abandonware sites are unregulated.
In 2021 (and continuing today), the original developer, Alan Lorence, and the current owner, Boris FX, made the decision to release ParticleIllusion 3.0 as a completely free download. This includes the full software license. Note: Always ensure you download such legacy content
But here is the 2021 reality: