This one is probably illegal to do but i did had fun doing it. basically what you did was to obtain a floppy disk and force it open,next you get a box of matches and scraped all the sulfur off of it and place it on the disk.your final task is to seal back the floppy disk with nail glue and the rest is up to you.
note:this illegal act requires the computer to have a disk drive so this trick is probably best done at school