Just saw an article about a radio controlled device which switches off all devices plugged into it. The idea is that you plug your TV, stereo, amp, etc into this adaptor and you can then switch off the socket (akin to clicking the power button on the socket), thereby reducing the power used by devices on standby, without having to get to the socket itself.
This seems like a great idea for devices which are plugged into sockets behind TVs, etc. I think I might get a couple when they go on sale next month.
It will go well with my OneClick adaptor which switches off everything plugged into the socket 5 seconds after my PC switches off - such as the monitor, speakers, printers, etc.