About a month ago while doing some hardcore overtime at work, I became obsessed with the Idea of being able to turn on my electric blanket remotely so that I could come home and go to sleep straight away. (a little sad I know...)
So anyway, my research on the topic eventually lead me to X10 Home Automation units, which aparently everyone but me had heard of before.
If you're one of the people who hasn't heard of it, its basically a standard protocol for controling the on/off state (among other things like dimming lights) by sending signals through your standard electrical wires.
So now that I'd found my technology, finding it in the 240v variety proved a bit trickier, but I eventually ended up at Whome.com.au who were cheaper than anywhere I could find in NZ, and have had excellent service so far.
I bought a USB control unit to plug into my iMac at home, and a few appliance/lamp modules to test it out with.
Setup was unbelievably easy after downloading Indigo 3.0 (mac based home automation software, as the unit only came with windows sofware). About an hour later I'm turning my lights (and electric blanket) on and off with my iPod touch via a web interface, and I'm a happy man :)
It sounds like when the iPhone 3G comes out there will be all kinds of people writing native apps for controlling this stuff, I look forward to automating my home further.