IIRC Andrew , neutral for 'rolling' uses fuel to keep engine ticking over , in gear fuel isn't used at all (momentum of the car keeps engine turning).
There is also the obvious tricks:-
Slow Down - over 50mph you use a lot more fuel just to break the air resistance of the car.
Keep windows/roof closed - Actually when in town and moving slow its better to open them than use the aircon.
Keep aircon off - As with the windows , if you are moving fast (motorways) then use aircon if it's that hot and not open the window a little.
Clean out the Junk - Yes I know you love your CD collection and your Garfield toy stuck to the window but its all weight you are paying to carry about.
Tyre Pressures - Check em regularly, Goodyear recon that 20% deflation of tyres is about 10% more fuel used. Increase pressures when you have the family in the car.
Use high gear - Engine is much more efficient at lower revs , as long as its not labouring
Anticipation - Seeing something earlier saves fuel , braking is just a waste of energy. Also you don't have to use all the gears to change down at a junction or stop.
Another big hint is shoes , dont wear them or at least wear very light and thin soled shoes. You can't control acceleration well (for hypermiling) in 'big' shoes