""A lot of times, it's evidence that will take you to your next step in the investigative lead, so it will tell us who this person has been in touch with or who they've been emailing or texting," said Richard Mislan, Ph. D., a cyber-forensic researcher at Purdue University in West Lafayette, Ind. To help dig up digital evidence and catch criminals, cyber-forensic researchers use a device called a flasher box."