Here are a few suggestions:
Cycle the AC on and off if you can. If you cool it down with AC and then turn it to just fan until it heats up again, you may reduce your AC usage by 50%.
Pop it out of gear after you reach your target speed so you coast in neutral, idling at speed. Drive Without Brakes (DWB), only investing as much gas as you absolutely need to get to the next light. And post your gas logs!
