Restrictive policies about what employees can put in their e-mail signatures deprive you of a useful source of information about your colleagues, says Kris Dunn. "By allowing employees to 'let their freak flag fly' when it comes to fonts and colors, you find out who the outliers are," he writes. "See an employee break out the Comic Sans in purple with a paisley background? That's all you need to know. Make sure the Christmas party is alcohol-free for this person."