Let's face it, with the ever-increasing gas prices and the government's lack of initiative to fund a good replacement energy source, we've been left holding the bag. For this very reason, many people have resorted to conservation and have started using gas mileage devices to lower their overall gas consumption. Here are a few examples of these gas-saving instruments:

1. Vapor Bleed instruments. These types of devices are installed near the engine compartment and bleeds air through a container of water and an anti-freeze mixture. Some examples of these tools include the Atomized Vapor Injector, the SCATPAC Vacuum Vapor Induction System and the Turbo Injection System.

2. Air Bleed Instruments. Similar to the Vapor Bleed devices mentioned above, Air Bleeders bleed air but this time they are injected into the carburetor.

3. Liquid Injection Devices, which add liquid into the fuel and air intake system instead of the combustion chamber.

4. Coolants for Fuel Line Devices. These nifty little devices prepare the fuel before it is entered into the carburetor. The coolant heats the fuel in order to take the load off the exhaust and the electrical system.

5. Ionized Fuel Line Devices. These are specialized devices installed in the fuel line and promote ionization in the fuel, through the use of several dissimilar metals.

6. Carburetor Mixture Enhancers. These gas mileage tools are installed between the intake manifold and the carburetor and do the job of improving the vaporization of the air/fuel mixture.

7. Liquid Mixture Enhancers. These things do the same job as the carburetor mixture enhancer, but are in liquid form and mixed with the fuel.

8. Various Engine Modifications. These are usually done to enhance the efficiencies of the engine, which means they would require less gas for propulsion. Most of these are done on old engines that are worn down because of age.

9. Various Fuel Additives. These types of gas mileage increasing additives vary in purpose and makeup, from liquid oil enhancers to lubricants to coolants, they are all lumped in this category as long as they are added internally to the gas tank.

10. Driving Aid Devices. These are by far the odd part of the bunch. Instead of helping the car increase mileage internally, these devices usually try to modify the driver's habit. For example, a light or sound device that alerts the driver if he is going to fast or suggests a shift in gears. The most expensive types are usually digital devices that also provide warnings for other instances such as leaving the door or the trunk ajar.

There has been much criticism thrown at gas mileage devices due to some manufacturers' claim that they can increase gas mileage by as much as 30%, even though the EPA has tested them and found only 12% to 25% increase in overall gas mileage. Either way, even though these devices were not able to live up to their hype, the 12% mileage increase would still go along way, especially in the long term. Just make sure to assess the total cost of some of the devices, if the savings on gas money will justify their cost.