Ranger band's won't work. Don't ask me why... I haven't a clue. I've tried every way I can think of to make regular Zippo's "evaporation proof". Even plastidip. No luck. However, I do like these Zippo fuel canisters:
http://www.theconnections.com/product_info.php?products_id=476
I've stored fuel indefinately in them.

I have also tested these "peanut" size flint lighters (Zippo principle):
http://www.countycomm.com/sslight.htm

Mine held enough fluid to light after 6 months hanging on the dash of my car. Even without fuel, the flint will light TinderQuick. I've stashed them all around my gear now.