The "Boys" like to change the Christmas Lights too!
One useful item for testing (and "messing" with the neighborhood kids! ;-) is
the X10 remote control. I have a wireless receiver plugged into an outlet
and with the remote, I can send commands to it that are then relayed
through the house wiring to the various X10 control units - all standard
X10 stuff. I don't let 'em do it very often, but my kids like to play
with the remote as can can be seen here.
Look closely at the upper windows
188.8.131.52 does a zoom in for us! ;-)
Here's what it looks like from inside the house! ;-)