This is my new homemade fireworks control panel. It can control 6 slats with 16 cues each. Each position on the rotary switch selects 4 cues each on 2 slats. I use this to have a left and right slat for many paired effects, then I might push buttons 1 and 5 simultaneously.

I've made two of these - one for my brother Jeff and one for me.

Update 2/25/2010: I added photos of a slat tester I just designed and built.