Here's my version of a crate beast / monster-in-a-box prop for 2009.  It uses a Prop-1 for control, an AP-8 for audio, and an RC-4 to switch the fog machine, the strobes, and one of the pneumatic cylinders.  It's triggered by a PIR motion sensor.

Video (daylight): http://www.youtube.com/watch?v=j3pXGikkCw4
Video (night): http://www.youtube.com/watch?v=m95ar-WPuYk

Expecting rain, I packed all of the electrical parts into a plastic Erector Set case and mounted that inside the crate.  It rained steadily on Halloween evening, but everything worked flawlessly!

Very nice -- we always love to see well thought out and constructed props like that.  Congrats.

Very nice!  Really like the wood finish and strobe effect.