It's easy and inexpensive to significantly reduce these phantom costs: plug your electronics into power strips and use the on-off switch on the power strip to fully turn off the juice when you are not using the electronic device or appliance. Even better, by selecting power strips that are also "surge protectors" you'll help prevent your valuable electronic devices from getting fried in electrical storms or power spikes.
Use a meter called "Kill-a-Watt" or "Watt's Up" to tell you how much electricity your appliances and electronics are using, even when turned off. Energy auditors use them as part of energy efficiency reviews for homeowners, and the results can be shocking. The top culprits for phantom electricity usage are: televisions, VCRs, cell phone chargers, computer monitors, printers, and video game consoles.
Fast-forward to minute 6:15 of this video to see a Kill-a-Watt in action.