According to a report in New Scientist, by comparing bugs found on a person's hand to those recovered at a crime scene, you might be able identify the perpetrator.
"There are certain situations where human DNA analysis or standard fingerprinting doesn't work, maybe this is just another tool," said Noah Fierer, a microbiologist at the University of Colorado in Boulder.
His team knew that microbial communities on skin tend to be unique to the individual and change little over time.
To see if these qualities could be applied to forensics, his team swabbed several computer keyboards and the fingertips of their users, then identified about 1400 different kinds of bacteria living on each, using DNA sequencing.
The keyboard bacteria closely matched their owner's fingertips.
In another test, Fierer's team were able to correctly match nine computer mice with their owners.
The "microbeprint" seems to be long-lasting: swabs left at room temperature for two weeks could be matched to their owners.
"But accuracy issues mean you won't see them used in court just yet," Fierer said.