How to save money on gas

Gas has been getting more and more expensive these days and currently, it costs about $3.46 for regular gas here in California. I was filling up my tank about once every 4 days before I moved closer to work. During that time, I have done several things to help me save gas money.

Gas Rebate Credit Card - I signed up for a Shell CitiBank MasterCard and within 2 months, I have already saved $31.41 in gasoline!! This card gives me a 5% rebate everytime I use my card at a Shell Gas Station. Considering that I only live about 10 minutes from work, I can still save about $200 a year. For those who drive more often than me, your savings will be even greater. Now, let’s do the math:$31.41/2 months = $15.71/month * 12 months = $188.52 in annual savings on gas =)
Gas molecules condense as temperatures get lower - I try to fill up in the morning or whenever it is cold out because gas is more dense at lower temperatures. This way, I actually get “more” gas per gallon. Although I cannot provide any scientific proof of this, I believe it is valid.
Lighten up - We all know that the heavier something is, the more energy (or gas in this case), it will take to get it moving. Take a look in your trunk or back seat floors or even under your seats. Many of us probably have useless objects that are just sitting around in our cars. For example, I currently have this 30 pound bocce ball set that is in my trunk just waiting for me to use, but I probably will not get around to using it for another couple of months!
Ski Racks - Ski racks will cause drag (or air resistance) when you are driving so take it off when you are not utilizing it. I heard that it will improve gas mileage anywhere from 10-15%.
Keep an eye out for gas prices - Usually, the farther a gas station is from a major highway, the cheaper it is. If you see a gas station that has relatively cheap prices, stop and fill up even though your tank might not be empty. GasBuddy is a good site that helps you locate the cheapest gas stations near you.
Keep the windows closed - Having your windows open will create drag and decrease your mileage per gallon by as much as 10%.
Easy on the gas pedal - Take it easy when accelerating from red lights or stop signs.
Take care of your car and it’ll take care of you - Under-inflated tires will increase the rolling resistance because more of the tire is making contact with the road. Keep your tires properly inflated according to manufacturer’s recommendations. This information can be found in your owner’s manual. Not only will this help with fuel economy but it will also increase the lifetime of the tire. Also, keep up to date with oil changes and maintenance services. Major maintenance services such as the 30,000 mile service should include cleaning of the fuel injectors. This will insure more economic use of your fuel.
Invest in a navigation system - I’m not sure about you, but I find myself getting lost once in a while. This obviously wastes gas. About 2 months ago (3/2007), I purchased the Garmin c320 navigation system and I have been very satisfied with it. It has received great reviews and I have been waiting for the prices to drop under $300. Not only does this help save money on gas, but it also saves a lot of time from getting lost and having to jot down or print out the directions.
Carpooling - Carpooling is a great way to save on gas. Ask coworkers or friends if they are willing to carpool. If you are having a hard time, you can try CarpoolConnect.com or eRideShare.com.
Buy a hybrid vehicle - Hybrid vehicles are getting more efficient and affordable these days. The 2007 Toyota Prius gets 60 city miles to the gallon with an MSRP range of $22,175-$23,070 according to Edmunds.com.