[Suicide Junkie]

Wouldn't a batch file or even just a shortcut do fine for that?

I have a little LAN helper program that does something similar for two players... (point it to two files, and when both are present it processes) Uses the numlock/capslock/scroll lock lights to show which files are present.
Its mainly for when you're just spamming turns back and forth, and best when both people have access to the savegame folder, such as a shared dir on a lan.