7. Fire

Please refer to http://en.wikipedia.org/wiki/FlashPaper for more information. Flashbills are available from many magic stores including http://www.penguinmagic.com/p/S14139.

Please refer to http://en.wikipedia.org/wiki/Carbide_lamp for more information.

Please refer to http://www.americanscientist.org/issues/pub/d-bereiners-lighter for more information.