This is a great gag to help smokers kick the habit or just have a few laughs.My friends have had a lot of fun doing this at a local cigar shop.
Step 1: Materials
All you need to pull off this little prank is some magician's Flash Cotton.This is a special type of chemically treated cotton that burns very quickly and produces a bright flash of fire. Flash Cotton is used by magicians to produce various pyrotechnic effects (readily available at your local magic shop or online).
Step 2: Preperation
Take a small wad of Flash Cotton and fluff it up with your fingers.Pull on the cotton and spread it out as thin as possible so it resembles a piece of lint. The more you fluff it up the quicker it will burn.Place it in an ashtray and then sit back and watch the fun.Even the slightest spark or cinder will set it off and result in a brilliant flash.The person's surprised reaction will provide you with hours of laughter and snickering.Don't worry about harming the person because Flash Cotton burns very quickly and with low heat.Enjoy!