It's only been in the last few years that the PC industry has started to recognise that it really ought to have a conscience about how much energy it is wasting. CPU manufacturers are fighting wars on how efficient their chips are and PSU companies especially are at least trying to be seen to fight the good fight.
One of the biggest wastes of energy in the home though, as we're always being told, is the standby button. Most electrical appliances have standby modes to allow them to start up faster, and your PC and monitor combo is one of the most offensive in wasted standby energy. Granted both of them together only draw 7W, but that's a constant draw.
The Bye Bye website is trying to put this out there as a money saving option, citing statistics that claim a saving of £40/year when using only three Bye Bye Standby devices. When the starter kit costs half that it's not a huge saving, but will pay for itself over time. Again though this is more of an ethical solution and the price isn't a lot for the ability to ensure that your appliances are drawing zero power through the wall sockets when not actually in use.
The plugs work in the same way as the Domia Homeplug kits, sending signals to the sockets in between the appliance plug and the wall socket to turn them on or completely off at the touch of a button. It's completely wireless and you can mount the switch anywhere you like for ease of use.
As a piece of simple green technology it's a winner - fairly cheap and incredibly simple to set up. The only real problem I have is that once the battery runs out inside the switch how many people are actually likely to make the effort to find a replacement?