Here is my version of the emergency party button. I owe credit to https://www.plasma2002.com/epb/ for the inspiration. I used an I-Pac to interface to the computer keyboard and used Autohotkey to run a macro that starts the music and runs a macro in Virtual Home Commander to control the X-10 items.
Cost:
X-10 modules: Given to me from a friend
Buttons/housing: Given to me from my father who got them from work
I-Pac: www.ultimarc.com Already had from several MAME Projects
Computer: Had
X-10 Firecracker: Ebay $8 or so
Post time: Jun-20-2017