Finally, with some help from my able assistant (who knows how to talk to the terminal window) I've gotten the process working, and put a large zoomable fractal online. If this one seems to work out all right, and doesn't give my web host trouble, I'll do some more.
This was one of my contest entries. I like the metallic texture that becomes visible when the picture is magnified, and I also like the sort of hunched, brooding quality of the thing. It reminds me both of the shipping cranes down in the industrial end of town, and of my cat, when she's tensely coiled and watching pigeons. Motionless, but with the sense that it might do something if you turned your back and didn't watch it too closely. Or that it's only standing still because it's been there for an enormously long time, in all sorts of weather, and all its gears and pulleys have corroded and fused themselves into immobility.