This is a super useful modification of a long run tim flash light to more than triple its lighting time. With a resistor and a soldering iron and this long run flash light you can have one that will last a long long time. Luxstar shares the instructions and after testing was able to run it for 24 hours per day for 15 days and could still read with it.
Luxstar
That is pretty amazing and would be well worth the time to do. Make one for yourself and one for everyone you care about and all for a pretty inexpensive price. Check out the tutorial on Instructables.
Click here for tutorial:
http://www.instructables.com/id/Easy-Flashlight-Mod-Increases-Run-Time-36X/?ALLSTEPS
