The number of electrical items in our homes just seems to keep increasing, many of them we wouldn’t want to do without. The same is true with PCs, with the growth in variety and drop in price of external peripherals more and more people are buying things like external HDDs and DVD burners. This also means you’re using more electricity as each device has to have its own power supply.
Make sure you switch them off each night and you could save yourself a bundle. Many of these devices are relatively low power, but they often also come with cheap transformer blocks and leaving them on can cost up to £45 a year on your electricity bill. Definitely make sure you switch off you monitor, especially if you have a CRT one (one of the big boxy monitors). A CRT monitor left in standby overnight for five years will cost as much as buying a more efficient LCD monitor.
Something that may well be investing in is a device like the Intelliplug which you plug your PC and some of your peripherals into and, when you shut the PC down, they will be switched off too. An easy way to save money.