Absolutely Theater - Forums dedicated to the discussion and operation of all things theater.
American Theater Web - Discussion boards relating to American theaters, musicals, monologues, broadway shows, and theater books.
Community Theater Green Room - Discussion boards with topics including theater resources, articles, how-tos, directing, props, set design, play reading, and humor about acting.
Educational Theatre Association - Discussion boards relating to the theatre and acting. Topics include scripts, technical matters, performing arts education, and the theatre for life advocacy campaign.
GayTheatre Exchange - Free networking site for dialogue, exchanges, and unabashed self-promotion for those involved with gay theatre, film, and music.