Karen McDowell spent several days this fall dressed in a purple fish costume, holding a plastic spear.
Ms. McDowell, a network-security analyst at the University of Virginia, wanted to raise awareness about “phishing,” e-mail schemes in which con artists send messages to trick people into giving out passwords or other personal information. Ms. McDowell walked around high-traffic areas of the campus to get attention. “Sometimes I introduced myself as a fraudulent e-mail because many people don’t know what a phish is,” she said.