That is a nice application, but remember that the X-10 RF signal is not a "coded" signal. Anyone with an X-10 RF transmitter can also turn on your lights and operate anything else in your home via the X-10 RF signal. The X-10 RF transceivers intentionally have limited range to prevent people from outside of your home from doing this.
A secure solution to this is to use a specially designed "code hopping" digitally secure remote. We offer one small keychain remote that is capable of sending 15 separate RF channels that are secure. The keychain remote can be used safely to arm/disarm your home security system, open your garage doors, turn on lights, etc. The frequency also allows great range.
You can find out more about this product at: [Link: ourworld.compuserve.com]