My brother came down today and we got to messing around in the garage. This is the end result...
Here's a really odd star shaped light we got for Christmas.
It's plugged into this four-way under the stairs:
Note the bright orange lawn-mower cable. The other end of that cable is here, in the garage:
That weird silver thing is called an inverter and basically converts 12v DC into 240v AC. As you can see here, it's all hooked up and into the whole car battery that's permanently being recharged by a solar panel:
As you can see it's already working hard charging up digital camera batteries and mobile phones. Now it's also doing this:
That's being totally lit by the car battery in the garage that is recharged from the solar panel on the porch roof!!!
I know that there are in-built huge in-efficiencies throughout the system. In an ideal world I'd pipe in 12v and use a million and one different in-car adapters for the phone and the laptop and I'd modify the light too. But in a practical sense, having a normal mains 4 way that runs off the system is much more useful...