Well, the John Bond way that is. Bond, the head of forensics at the Northamptonshire Police in the UK, has devised a way to fingerprint bullets with electricity.
He discovered that the extreme heat that occurs when firing a gun causes salt from a fingerprint to slightly corrode the casing. By zapping it with electricity he can detect these prints years after the shots were fired. In fact, Bond was recently able to identify prints on four shells from a 1999 crime scene in Georgia and his method is now in high demand. The hope is that hundreds if not thousands of cold cases could be re-opened and solved thanks to this technology. [BBC via Wired]