There's an urban legend in the tech community that goes like this: The School of Computer Science at Carnegie Mellon University used to keep track of how many of their undergraduates were men named Dave versus how many were women. And it was considered an accomplishment when they got the ratio down to one Dave per woman. Today we're starting a new series about the tech industry's diversity challenges, called "I am not a Dave." In the first installment we take a look at a group called Lesbians who Tech, which holds its first summit this weekend in San Francisco. Plus, Taser International, the company that makes the famous weapon, is transitioning into offering new law enforcement tools in the digital space.