Things to do instead of Earth Hour (that will acutally make a difference)

This post is under construction! New edits as of March 26, 2011 are highlighted like so! Even newer edits from March 25, 2017 are highlighted like so!

1. Unplug and sell or donate your "second fridge" and learn how to use your main fridge efficiently. Use the freezer compartment of your fridge rather than having a deep freeze. Grow your own vegetables so that you can harvest them as you need them, without having to store and refrigerate them. Learn about which produce items do not need to be refrigerated at all. If you would like to freeze your excess produce for use during the winter, consider only running your deep freeze during the "off season" as your storage volume increases. If you have enough room in your fridge freezer, use that instead.
2. Unsubscribe from cable or satellite television. Netflix or CraveTV are cheaper than cable packages and can give you the option of keeping up with your favourite shows... That way, your TV will only be on when you are watching a movie or playing console games. Once you adjust to not having the TV on constantly, you'll be amazed at how much you don't miss it. Also, an HD cable box pulls about as much power as an average laptop computer, or a 17" LCD computer monitor. So if you must keep your cable TV, turn off or unplug the box when you're not watching.
3. Replace all of the incandescent lightbulbs in your house (as they burn out) with compact fluorescents or other energy efficient bulbs such as the LED options that are now more affordable than they were in the past. CFL blubs use approximately one quarter of the power to produce the same amount of light as their incandescent equivalents. Check out this comparison chart!
4. Always turn off the lights when you're not in the room. In order for it to "take more energy to turn back on than you would have used by leaving it on" you would have to leave the room only for a fraction of a second. So unless you're Superman or The Flash, turn em off. If you're worried about wearing out your bulbs before their appointed time, switch to the longer-lasting compact fluorescents  or LEDs, which don't have fragile filaments like incandescent bulbs do.
5. If you want to have a light on when you come home at night, use a timer instead of leaving the light on all day. You can get an outlet timer for under $15 CAD at any hardware store. Program it to turn on shortly before you're scheduled to arrive home and to turn off again at around your usual bedtime. You can always manually turn it off as well. These are also handy when you're going on vacation and want to create the illusion that there is still someone at home. You can also get timer lightswitches to install in place of your existing switches, allowing you to program your overhead room lights to turn on and off at specified times. The last one I saw ran at around $50 CAD at Rona. You could also invest in a smart bulb, which is programmable to adjust the light's colour output, brightness, and on/off status automatically or on command via a smartphone app.
6. Use your toaster oven for baking small items like a small batch of cookies, brownies, one or two portions of fish, meat, or fries, etc. Basically if you can make it fit in the toaster oven, it's best to bake it there; A toaster oven uses about 1/2 to 2/3 as much power as a conventional oven to provide the same amount of heat for the same amount of time.
7. Eat more raw foods. The less heating, cooking, blending, microwaving, and food-processoring you can do, the lower your power bill will be! Also, fresh, unprocessed food is delicious, and good for your body!
8. Keep a vegetable garden. I know I mentioned this in the fridge thing, but seriously. If you grow it yourself, you don't have to worry about where it's been, what kinds of pesticides were used on it, transporting it home from the store, or disposing of packaging. Also, vegetable gardens help with important environmental things such as nitrogen and water cycles, reducing carbon dioxide in the air, preventing soil erosion, and maintaining urban biodiversity. Even if you don't have a yard in which you can plant a garden, you can grow food in containers.
9. Turn your thermostat down to 18 C. Use sweaters and blankets if you're chilly. Seal any drafts in your home (this is a tough one at my place, the whole building is one big draft, it seems!) and make sure your furnace filter is cleaned or changed regularly.
10. When the weather is temperate enough (above freezing), use portable space heaters to heat only the room that you are in, rather than using central heating to heat the entire house. This works well on rainy miserable summer days, chilly summer nights, and in early autumn or late spring in my part of the world.
11. Dim your computer monitor. Seriously, you can still see what's on the screen. Especially if you're not in an unnecessarily brightly-lit room.
12. Replace your bulky old CRT monitors with LCD monitors; They use less than half the power for the same sized screen. Either wait to do this until you're buying a new monitor anyways, for whatever reason, or donate the old one to someone who can use it, tuck it away to use as an emergancy backup if you have storage space, or take it to an electronics recycling centre. If you've taken anything to the Cloverbar Landfill and driven up to the main dump sight, you've see the "Great Wall of Japan" -- the massive fence made entirely of stacked-up CRT monitors and televisions!
13. Use a dark-coloured background on your desktop and on any websites that allow you a choice. It takes less energy to display black than it does to display white.
14. Walk, cycle, or take public transit whenever possible. If you live in a major city, there are VERY few instances in which a private motor vehicle is actually necessary. On the rare occasions when a vehicle is actually needed, you can take a cab, borrow a vehicle from a friend or family member, or rent a vehicle for the required amount of time. These things are actually more economical than owning and maintaining a vehicle year round, especially with fuel prices what they are. Pogo Carshare offers a convenient by-the-minute rental option in Edmonton. Use promo code RNECY when signing up to get 30 minutes of driving time for free! (Full disclosure: I will also get 30 minutes for referring you. Thanks for your support!)
15. Compost. It is mind-boggling the amount of compostable materials that end up in landfills. You can compost most kitchen waste (as long as it's not meat) including paper towels (used to mop up spills, not ones used with cleaning chemicals), coffee grounds and filters, teabags, fruit and vegetable peels, rinds, and cores (careful with seeds though, you might get some volunteer plants!), shredded paper (especially newsprint!), eggshells, and some new plastics made from corn (they usually say "biodegradeable" or "compostable" on them), as well as things like nail clippings, pet hair, the soiled woodchips from your hamster/guinea pig/mouse/bunny/other small furry animal's cage (avoid composting the feces of omnivores and carnivores though), and the inner cores of certain types of diapers (again only urine here, human feces is not healthy compost material).
16. Choose to buy items with minimal and/or biodegradable packaging.
17. Drink tap water.
18. Air-dry your laundry.
19. When you must use the dryer, clean the lint trap before EVERY load.
20. Set your washing machine to use warm or cold water instead of hot.
21. When it comes time to replace your furnace, hot water heater, and household appliances, look for energy efficient options! They may cost more out of pocket, but will save you money on your energy bills in the long run!
22. Take cooler showers. Especially in the summer! You don't need a scalding-hot shower to get clean. You can still be comfortable and use a tiny bit less hot water.

More suggestions and links to resources are forthcoming. But right now, I need to do homework and get some sleep.