The Briar Street Theatre has been turned into the "Blue Man Theater" since the fall of 1997. The avant-garde New York City performance phenomenon known as Blue Man Group has transformed the 625-seat theater, beginning with the lobby, which is now a jumble of tubes and wires and things approximating computer innards. The show -- which mixes percussion, performance art, mime, and rock 'n' roll -- has become an immensely popular permanent fixture on the Chicago theater scene (note to those with sensitive ears: It can also get pretty loud). The three strangely endearing performers, whose faces and heads are covered in latex and blue paint, know how to get the audience involved. Your first decision: Do you want the "splatter" or the "nonsplatter" seats? (The former necessitates the donning of a plastic sheet.)