Gas is hovering around four dollars a gallon and sometimes driving less isn't always an option, so here are a few ways to save on gas.

How much junk is in your trunk? My dad always jokes with me and says I drive a rolling dumpster and that if I "got rid of all that crap", I'd probably get better gas mileage. I always thought he was kidding around, but it turns out that Father does know best. If you're lugging around a bunch of stuff that you don't need all the time like golf clubs, sand, a case of oil or any other junk, you can increase your gas mileage by one percent. It may not seem like a lot, but it adds up.

How do you run your errands? Do you go farthest away and then work your way home or do you start close to home and work your way across town? Popular Mechanics Magazine says that a warm engine is most efficient, so it's best to drive across town first and do the errands that are the farthest away and work your way home so your engine doesn't have time to cool down. That way, when your engine is warming up (which is really tough on the car) you aren't starting and stopping constantly.

Speaking of smooth sailing, using cruise control on the freeway is best for increasing fuel mileage. Your car gets the optimal gas mileage at 55 to 70 miles per hour, so use cruise and stay within that speed range.

Is there anything better than driving on a nice day with the windows down? If it's a nice day and you're just darting around town, turn off the air conditioner and roll down the windows. The air conditioner sucks power so your engine has to work harder and you get lower gas mileage. The opposite is true, however for when you're on the freeway. If you're doing over 40 miles an hour, open windows create drag, so then it's best to roll up the windows and turn on the a/c.

It's also a good idea to have your tires properly inflated. It reduces wear and tear on your tires and gives you a nice smooth ride which your car likes and in turn will reward you with better gas mileage.

Do you have any tips that aren't on this list?