I was curious to when you're pumping gas, and you have those last 5 or 6 drops that you wait there for, how many miles do those drops actually convert into?
According to this website: http://askascientist.co.uk/physics/many-drops-water/ there are 90,922 drops (rounded up) in 1 gallon of water. Let's say you get 35 mpg in your car, each drop is 3.849453377620378e-4 miles. or about 2 feet per drop. So those 5 or 6 last drops you're waiting for will get you about 10-12 extra feet.
I paid for those feet, so I'll wait for them.