You have to click and drag around the black part of the screen, not completely obvious. I only found out when I got mad and started clicking stuff insanely.
Neonflames? I get what appear to be more like galaxy clusters. But still very cool. I like the way they seem to grow organically after you click rather than instantly draw.
I thought it wasn't working at first because I didn't notice anything happening... after clicking randomly for about a minute I started seeing colors. Simply stunning result :)
>It would be interesting implement it as a dynamic background to something.
Exactly the first thing I thought, since I've been looking for something like this to build interesting random desktop backgrounds that change very gradually but frequently.