A "roll call" thread is a topic in a discussion group that inspires many members to register a comment, like a virtual roll call. "Roll call" threads can be innocuous, like a straw poll to find out how many people could raise a single eyebrow, one of Xena's trademark expressions. The topic of National Coming Out Day and a related thread I called "Heterosexuals for Subtext" also inspired a "roll call" response, bringing lurkers out of the woodwork to register an almost obligatory response.