We often think of data traces in the online world, but what about the data traces we leave behind as we move through physical spaces? Forensic technology has become so advanced that traces of DNA left behind on cigarette butts, chewing gum or loose hairs, can be used to identify your sex, hair and eye color and even your geographical ancestry. Heather Dewey-Hagborg is an artist working on questions of data and DNA. Here she has created a company – Invisible – that makes sprays that allow you to hack, or erase, the traces you leave behind with just one spritz. As we enter an age of biological surveillance, bio-hacking meets cybernetics is no longer science fiction.