Gay rights activists in San Diego and elsewhere, hoping to sustain a grass-roots protest movement launched after the Nov. 4 passage of Proposition 8, have planned a nationwide boycott tomorrow. The event, called Day Without a Gay, encourages gays, lesbians and their supporters to take off work, refrain from shopping and spend the day volunteering somewhere. “We're hoping to provide a visual representation of who we are,” said Sara Beth Brooks, an El Cajon bookkeeper who recently formed a group called the San Diego Equality Campaign. “We're your neighbors, your family, your friends. We're everybody. We hope this kind of...