Double reserve trick
The first time I tried it was also the last time. I had turned only the left side on and got 25 miles further just on that side so when it ran out and I switched the right side over I figured I was good for at least another 15-20. Not quite, I got to call my wife 5 miles later from the side of the freeway. Luckily I wasn't all that far from home and it was a Saturday, bad part was I had to get my wife out of bed..........