I believe I may not be the only one to empathize with D. Carment.

I've run out of gas (at least once) in each van I've owned. :(

I learned to identify the point where the needle was when I ran out, I mark 
THAT point on the indicator as the PANIC LINE!

I've got a set of gas containers now because, for each van, I purchased a 
gan container that will fit in some unobtrusive place.  For instance, in 
the Eurovan ... I purchased two 2 1/2 gal containers and have them 
positioned below the rear seat and behind the tool bins. Fits very well and 
gives me the peace-of-mind that if I miss my 'mark' on the dash that I will 
have 5 gallons to get me some place other than where I am, at the time.  I 
also have AAA coverage but the spare gas seemed to be a trade-off for the 
time lost waiting for assistance to arrive.

Of course, when I made that decision I was in a unilateral-thought-mode.

If any of you have a better suggestion, let me know.

* * * * * * * * * * 
Pete Sellers
"Constant And Never-ending Improvement"