We have one of the current cost meters that are either available from e-on or for purchase direct from Current Cost or eBay.
The meter monitors domestic electricity use via a wireless connection to an inductive clamp attached to the mains cable near the electricity meter.
The unit is very easy to set up and a USB cable can be purchased for connection to your PC. Free software written by Dale Lane The software is
here The cables can be purchased
hereYou can export the data and manipulate it however you want and even connect to the web to compare data with similar situations to your own. It really does make you think about your power usage!!
I am also using one of the e-on powerdown plugs.
This unit offers surge protection and also shuts down connected peripherals once it senses that your PC has shutdown, thus saving standby power. These are also available cheaply on eBay.