In addition to the IR543 and lamp modules you might consider getting the CM11A device that will hook up to your computer. From your computer you can upload a macro to the CM11A device that will do what you're asking with only a single X10 signal sent (ex. A 1 ON which is actually three button presses so you'll probably want to program that as a macro). I use this setup to control a CD player on my computer (this requires a permanent connection to my PC which is no big deal), various lighting scenes in my room and a "light show" in my living room.

David