Gentle Acceleration
Keep your revs lower for longer, means less fuel burnt.

Keep the Revs Low
Get used to the feel of your car, with a little attention, you'll feel when the revs are too low, and also where it is just out of comfort. for me the sweet spot is the low 2-3k range over and I change gear.

Try 5 below the speed limit
You won't notice the difference in travel time, and your stopping distance will be slower

Switch the engine off
Intersection of a main thrououghfare? The guy at the toll booth in front of you is having an argument with the cashier? traffic is backed up for as far as you can see? turn the engine off! According to another site I read, restarting the engine does not require significatly more fuel. NB Some models of car will lock the steering wheel when the car is switched off. Make sure you do not switch the engine off in situations where you require steering.

Stop Accelerating sooner than you normally would
I don't know how many times I have hit the gas to get up an onramp onto the highway only to brake 10 seconds later as I get too close to the car in front of me. Stop accelerating sooner slip into neutral and see how you go.

Change to Neutral
You are running down a hill, you have plenty of space ahead of you, and no cars behind you. if you look at your rev gauge, you may find that even though you do not have your foot on the gas, your revs are still high. This is because the wheels are forcing the engine to turn, slowing you down, and consuming more fuel. Slip into neutral, and watch your revs go down. Bear in mind you are less in control of your vehicle in this state, and be extra vigilant for situations in which you may need to accelerate. Please note, this one is somewhat contentious, for more detail, click here.

Don't use your engine as a brake
When you do this, the wheels force the engine to turn over faster, your revs go up, so does your consumption

Only fill Half your Tank
Filling up with only half a tank instead of a full tank will give you less weight and better fuel efficiency (if keeps the psychological impact of the cost down too). (Thanks to Mike for this tip)

Unleaded vs Premium Fuels
There is debate about this one, tested on numerous TV shows like Mythbusters etc. Is it really" better to burn out than fade away?" My view is that there may be more energy in high octane fuel but it get consumed faster. A number of the TV tests show the lower octane fuels being more fuel efficient. As for me, I love the extra 'tiger' in the tank, and think its good for the engine, I put optimum fuels in every 3rd or 4th time I fill up. Check the pitfalls page for and additional tip re high octane fuel. There are also varying idea's about this tip, click here for more info

Maintenance
Sure there is stuff you can do when you drive, but the better maintained your car the more fuel you can save, do you know that not having your tyres inflated to the correct pressure uses more fuel? I have heard figures on 10% for each 5KPA under. Additionally, a clean air filter helps reduce fuel consumption (more oxygen in the mix?)

Tyre (Tire) Selection
There is a tyre manufacturer where I live that makes silica tyres they claim save 7-10% on your fuel bill by having a lower 'rolling resistance'

Plan your route - Schedule your day
There are two main factors to consider to reduce your fuel consumption, don't drive as far, and don't spend a lot of time in traffic Knowing where you're going, combining multiple trips into one trip, and finding a more direct sequence in which to run your chores all helps.

Use a GPS - and go the other way
I have a couple of GPS, I love them. Much to my wife's disgust, I use the GPS even when going to a nearby store (I like my extra speed readouts ok?). The great thing about the GPS - you always know where you are, and where you're going. My unit allows me to chose faster route, or shorter distance. I always have faster route set, but shorter distance could lead to better fuel efficiency (you may have to take some funny shortcuts!) Here is the thing I have noticed. The GPS most often routes me via main thoroughfares, which is a good thing, however, these routes tend to have more traffic! Sometimes a small variation of your route (take a secondary road that runs parallel to the suggested route) can give you a good route, but without the traffic congestion.

Cycle or use other modes of transport
Believe it or not, it's faster and healthier for me to cycle in to work than drive.. so catch a train and read a book or exercise.
(David Brunelle suggests www.bikestation.org has some good resources)

Live close to where you work
If you can arrange your lifestyle in such a way as to minimise your fuel usages then this is a good option (thanks to Olenga/Phoenix for the tip)

Eco friendly vehicle
There really is no longer any excuse, the technology is improving every day, it's just a matter of which version you prefer.

Fill up on Tuesday.
Of course the petrol companies don't collude on prices. Of course they don't put prices up as soon as a barrel of crude goes up, and then not drop them down after the price drops, but you'll notice that it's cheaper to fill up on certain days than others, going on a road trip before easter? You may find the price higher just before or just after the holiday. The price of fuel fluctuates weekly, seasonally, and with geo-political markets. The cheapest day to fill up in my city, is Tuesday.

Weight
Get a lighter car, not a tank. Take heavier items out of the boot if you're not using them.

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