Researchers from Jordan have developed a biometric identification technique that can pinpoint people by the V-for-victory hand signs they make. By measuring finger points, the gap between them and two palm points, scientists can identify someone even when there are no other telltale cues. In some cases, it was more than 90 percent accurate. Here's the link to their paper: http://arxiv.org/ftp/arxiv/papers/1602/1602.08325.pdf