Via Bruce Schneier:
Here, we develop an approach to translate chemistries recovered from personal objects such as phones into a lifestyle sketch of the owner, using mass spectrometry and informatics approaches. Our results show that phones’ chemistries reflect a personalized lifestyle profile. The collective repertoire of molecules found on these objects provides a sketch of the lifestyle of an individual by highlighting the type of hygiene/beauty products the person uses, diet, medical status, and even the location where this person may have been.
Perhaps the next level beyond this will be similar type of analysis of the air around you. Imagine going through airport security and the scanning machine blows air over you and determines your health, how recently you fired a gun, what pets you have, your DNA as well as that of your spouse, children, and mistress.