Hundreds of liquids, from fruit juices to specially formulated chemicals, can be used as invisible ink. Here we explore six of the most interesting and accessible types. We hope you’ll be inspired to make your own invisible ink at home. With a bit of practice, you too can become a master of steganography (which is the art of writing hidden messages, in case you didn’t know that already!)

How much money does a professional steganographer make? Link -via Geek Like Me