Some tips (for those who didn't see the earlier post):
1. Plan those trips.
2. Use more efficient cars.
3. Maintain older cars properly (they can be very efficient too).
4. Bicycles for short trips.
5. Car pools.
6. Load gas at night.
7. Park in the shade
8. Instead of idling to warm up, travel the first few hundred meters in low gear.
9. Avoid jackrabbit starts.
10. Don't race on the streets; leave that for the track.