Same boat here... Mine's an ubuntu loaded Micro Server that's on 24/7 and gobbles up telkom packets 
X10 controllers... hmm.. lemme go google that
If you want to go ALL the way with home automation mixed with Media center stuff, look at LMCE
We joke a lot saying this or that can do everything except for making coffee.
Well LMCE CAN make you coffee as well. It takes your media center, and put's in in charge of your home. Irrigation... SOrted. Light dimming when the movie starts.. sorted. Your Climate settings can follow you where you are in the house. The media you are watching... Yes, that can follow you as well. That LMCE solution is INSANE!
Pitty it was too complex for my wife.