MSNBC has a quick and simple list on things that you can do to help you save money and the planet. They have a list of 10 carbon-reducing actions that you can take if you own a house and a car. Those who have neither may not find this list that useful, but there is a bonus tip #11!
From the list:
10. Think about your refrigerator. Don’t locate this particular appliance in direct sunlight or next to the stove or dishwasher. Also, unplug that extra fridge, especially if it’s just keeping a six-pack cold.