This last Halloween and Christmas I got to experiment around with the Light-O-Rama. It is a device that lets you control AC current to up to 16 devices per box. You can link more boxes together via a network to extend this up to at least 256 connections.
Here is the result of my Halloween mix from 2012.
I am using a single 16 channel Light-O-Rama commercial grade. It requires 30 amps so it has to be plugged into two 15 amp AC outlets. I run an RJ-45 Ethernet cable from the box to the inside where it is connected to a micro mp3 player. The mp3 player has a micro SD card inside it with the play list and all the sound tracks along with the programmed sequences for tracks (making the sequences is the fun part and I will discuss that in a future article.)
One of the channels goes to a 750 watt Macho Strobe, you can see it a few times in the videos on the right side of the house but it is off screen. Two more channels are used to coordinate 6 strands of purple and orange led lights. Another channel controls the cauldron and flame on the porch, and the rest of the channels go to the 16 pumpkins (some pumpkins share the same channel.)