Many items use more electricity than you would expect. They even suck down electricity when they are turned off. If there is a device which you aren't going to use for more than a few days, try unplugging it.
If you do this everywhere you can it will make a noticable difference in your electric bill. Doing this and turning my thermostat up to almost 80 during the day when I am at work (I am an Air Conditioning freak, I need it to be 69 degrees at all times) have saved me over $100/mo on my ridiculous electric bill!