Update - I use many hypermiling techniques but mainly it's just the usual defensive driving - looking ahead and anticipation, trying to drive without using brakes (wasted energy), driving with load, coasting in 'N' with engine on or off depending on circumstances, slow down, etc.
Since I got the UG, I've managed a 720 mile tank compared to my previous best of 638 and it's probably improved overall fuel consumption by 15% just knowing what the numbers are!