An average person who uses a computer would usually just walk away from it when your done, or if your gone for an extended time (and they know about it in advance) they'll probably put it in sleep . I (myself) use to keep my computer on about 8 hours a day, just saying I'll comeback to it later. Well there are many ways to save electricity.

Step 1: CRT Versus LCD

Many people and businesses use CRT monitors because they might have it from an old computer and say "Hey, why buy a new monitor works just fine, I'll save money."

Facts about an average 17" monitors (using the average kwh price of 9.86 cents, you can look at the map):

CRT
1) Electricity used: 80 watts
2) Money spent keeping the monitor on for 8 hours cost about 6.4 cents per day, which adds up to 23.36 dollars a year.
3) Cheapest new I could find off of Newegg was 125 dollars.
4) They're fat and ugly and take up half of your desk (well that was an opinion)

LCD
1) Electricity used: 35 watts
2) Money spent keeping the monitor on for 8 hours cost about 2.8 cents per day, which adds up to 10.08 dollars a year.
3) cheapest new I could find off of Newegg was 150 dollars

So if you have a CRT and switch to a LCD an average would save 13.28 dollars. If you had a choice of buying the CRT and a LCD you would only lose 11.72 dollars. A cheap price to help the Earth and have more room on your desk.

Step 2: Type of Computer

This part is usually ignored, because everyone has a personal preference, but this is just here so you know:

In order of electricity use from top to bottom (top uses the most)

PC Desktop
Mac Desktop
Laptop

Desktops use between 60 and 250 watts of power, laptops use 15-45 watts

I'm not sure about linux systems, they're probably either the most or second most efficient.

I use a PC desktop, I like PC's cause I think they're faster and have more compatibility. Sorry Earth!

Step 3: Standby

Standy by on an average computer takes about 1-6 watts, huge improvement on a computer idling. If your going to be away from your computer, put it on standby.

(Someone please verify the following paragraph, because I'm not 100% sure)
An alternative to standby is Hibernate. Hibernate basically writes all the things on your RAM to your hardisk. Then the computer "shuts down". Whenever you "turn on" your computer it'll bott faster than when it's really off and you'll have all of your settings back, just as if it was on standby. I think Hibernate is even more efficient than Standby.

To put your computer in Hibernate on a PC
1) Click Start
2) Click Control Panel
3) Click Appearance and Themes
4) Click Display
5) Click Screen saver
6) Click Power
7) Click on the Hibernate Tab and hit OK
8) Click the check box next to enable Hibernate if it isn't checked.
9) Close all of those windows
10) Go to the shutdown menu
11) Hold shift and Hibernate will replace Standby.

Step 4: Screensaver

Screensavers act as if the Screen is still fully on, don't use screensavers!!!

Step 5: Pust a Button

See that button with a circle and a line on your monitor? If you push that button when your computers off you save at least 5 watts of power!

Step 6: See How Much Power We're Saving

This summerization will not include changing your computer

Switching to a LCD monitor: 45 watts
Puting your computer on standby/hibernate: 59 - 244 watts
Turning off your monitor: 5 watts
Screensaver: No savings

If you have a CRT you should switch to a LCD, lot of power there.

Over all if you do all of these changes you could save up to almost 300 watts! If you have 2 or 3 computer in your house it could add up to 900 watts, if you run a business that has 100 computers that leaves your computer on overnight you could save 3000 watts! By taking a couple of second of your life and putting your computer on standby or off you could save up to 300 watts.

Step 7: Why Do It?

If everyone doesn't be lazy and spend litterally seconds putting there computer on standby, or gets an lcd screen you will be saving a lot of electricity! Come on! Do it for the Earth!!!