Ever since Steppenwolf famously got its start in a church basement, Chicago theater artists have made a practice of turning absolutely any room you give them into a performance area, where actors and designers work their magic three feet from your face. Sometimes these found spaces are especially hidden. Entering Bucktown’s 45-seat Trap Door Theatre (1655 W. Cortland St.) requires walking down a long gangway and, briefly, through the kitchen of a working restaurant. At other DIY theaters, the outside world can intrude when the walls aren’t thick enough to silence the L rumbling overhead or music from the bar next door. I once saw a play at Wicker Park’s Den Theatre (1331 N. Milwaukee Ave.) while a street festival raged outside. As the audience and actors psychically bonded together to blot out the metal band whose set coincided with the matinee, I thought: This is Chicago-style theater.