Funny I found today a prog (free) chaospro

there is on the site all progs about that !
http://www.chaospro.de/scripts/related.php

Take a look at the Mechanical Gallery ;)
http://www.fractal-recursions.com/

For real time exploration! Xaos free (increase the zooming speed to 5 ;)
http://wmi.math.u-szeged.hu/xaos/doku.php

The more funny and easy and gratifiant is Chaoscope ;) (free)
http://www.chaoscope.org/
File/New
F3 Start (Press any time you want for a new random parameters)
F4 Calculate
Esc Stop
I don't resist to make another one at each time I name it :D