Sorry to jump into your thread (and I don't want to put down the I-zombie unit you have), but I've been able to get great looking "flash/lightning" effects with a Chauvet sound activated strobe light and a simple thunder audio track, and it comes out to be a fraction of the cost of that I-zombie unit. (that's what I used last year and everyone that saw it was really impressed. they kept asking me how I was able to do it)
The Strobe I used.
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http://www.chauvetlighting.com/fixtu...000s_fix.shtml
(that big strobe cost me $60) I have it set to to mid way for the flash count (around 4-5 flashes per second), and when the thunder audio track sets off the strobe, it gives me a few quick flashes and then goes into stand by mode until the next thunder effect sound. It really does look like real lightning when it's activated. I'll see if I still have the short video I took from last year showing how it looked.
Oh, and American DJ also sells a simular sound activated strobe. (I think it's called "Big Shot")
As for light/sound controllers...
American DJ sells a few different sound activated light controllers that can probaly do something simular. The cost? Much cheaper than the I-zombie one. (I've seen thses selling for around $100)
http://www.americandj.com/product.as...og_Controllers
http://www.americandj.com/product.as...og_Controllers
And they also have the Light Copilot (II or III) which can do a bit more but also costs more.... (for around $150 -> $200).
Chauvet also sells strobe/light controllers that would probably do the trick as well.
http://www.chauvetlighting.com/fixtu...ller_fix.shtml
http://www.chauvetlighting.com/fixtu...ller_fix.shtml
http://www.chauvetlighting.com/fixtu...ller_fix.shtml
Again, sorry to post in your thread.