How can I use my computer to control my house?

I would like a way to use my computer to control the lights and appliances in my house.

Does anyone have any good suggestions on how to do this. I would prefer to do this as unobtrusively as possible. Ideally I would like it to be completely hidden.

Bonus points if you know a way to do this with voice control/speech recognition.

http://www.instructables.com/id/Control-lights-in-your-house-with-your-computer/

Here is a tutorial on controling lights with a computer.

http://www.gadgetmadness.com/archives/20040320-computer_control_your_house.php

Web store dedicated to home automation products: http://www.smarthome.com/

One other product solution that mentions light and appliance control:

http://www.x10.com/products/x10_ck11a.htm

X10 is a costy professional switching system, with quite limited capabilities (no automatic cat feeders or a cat cam for example).

So you might consider playing with Arduino www.arduino.cc This is a small stand-alone "computer" that can be programmed with ease over USB. The nice thing is that Arduino does not use much power compared to running a full PC. It is so small, you can hide it wherever you like.

From the basic Arduino, you can add several shields to switch appliances. There is a relay shield for 110/220V switching You can make Power-Mosfet shields for high frequency 110/220V switching You can add an XBee shield for wireless control of other XBee switches. There is a big bunch of input shields to read RFID, measure temperature, measure light, sample sound etc.

Pricing is great. Arduino costs around 20$, most shields do a similar price, and if you can solder you can cut on costs even further.

A good source for arduino projects is: www.makezine.com They have a nice store too: http://www.makershed.com/SearchResults.asp?Cat=43

Good books on the subject are "Making things talk" and "Getting started with Arduino" If you buy the Arduino starter kit, you have a great set of components to start with automation, and the nice book "Making things talk" is included as well.

This might be something you're looking for

You could use the X10 control systems above, and then cause specific application commands to be fired upon voice recognition using e-Speaking.

If your'e cool with programming, you could try writing your own custom program/script to pick up SAPI events based on your own CFG and then attach that to a library to send out X10 Firecracker commands, but that's seems like a bit much.