A while back I asked about a fuel gauge for the lack of a trip odometer....
Folk chimed in with some GREAT ideas/advice. I really like the after market add on that also has turn indicators, as I can't count the times I leave them flashing, ARG. Something to see (as I wear hearing aids which I remove when riding) more up in my forward site line I will add someday, for I feel its a important safety issue. But back to the gas thingy....since buying and latching on one of those cheap luggage combo locks as suggested here, and looking at the last recorded numbers from the last fill up, as I mount to ride anew, I haven't even had to flip it to reserve, much less run out again  

A great tip from a great and helpful resource (site).....THANKS!

The simplest, easiest to do, most effective and cheapest is a grease pencil. Just write the mileage +100 on your mirror when you fill up in 3/4" high letters. Every time you get on the bike, and periodically as you drive compare the mileage on the odo to the mileage on the mirror. When they start to get close to each other look for a gas station. I tried the luggage lock thing and found it difficult to read while riding.