Kinda... but there's a twist. The clouds that move up do not stay the same. I made four layers of uniform noise clouds, then mixed them up to create two "joining layers" between them to create more seamless movement from layer to layer. These layers were 1024x1024. When that was done, I copied squares first from 0,0 to 512,512, then from 0,40 to 512,552 and so on, moving the selection downwards so that the clouds appear to move up on the fire, like flames do.
Anyway, then I just applied a mask wit white center and black edges, set a suitable layer mode (don't know what it is in English

), and then copy each composite frame into another file. Now that this was done, I applied the automatic contrast-maximizer (whatever it is in English version of GIMP I don't remember...), then applied Incandescent gradient to every frame and finally a 2pixel Gaussian blur. These GIF's are 256x256 versions of originals.
The method seems to be working a bit better on tileable version; the soft-edged version looks a bit goofy when clouds are emerging from the lower edge below the actual fire starts...

I'd like to see what others' view on fire is. We can't have a decent flamewar with only one guy making flames, now can we?
