Step 1: The Case.
With the Help of a Jewelry files and a pointed Pliers, remove the guts and made a hole, so the USB Flashdrive Fits so nice in the Gas Container.

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http://www.instructables.com/id/Lighter-USB-flash-Drive/
Nahhh...I like it better my way...besides I used the metal Parts to another kind of stuff...but anyway...thnks 4 ur comment...I like the "Silly" part.
cos you could dremel off some of the end off the lighter to use as the cap for the usb and then dremel out the inside till your usb fit. put it in there hot glue it. cut out a section of eraser to fit the usb head hot glue it in the 'cap' or glue your old cap in there keep a bit of flick in there for fun and BANG your done. if i make sense
:)