Old-fashioned Broadway is moving into the digital age. New shows depend on million-dollar multimedia displays like never before, bringing video upstage after years of being relegated mostly to backdrop status.

New musicals like "Sondheim on Sondheim" use sophisticated swirling computer screens that flash thousands of still and moving images and are central to the storytelling action.

"Sondheim" and productions such as "Everyday Rapture" feature YouTube for comical effects. "Sondheim," for instance, includes a montage of people, from celebrities like Barbra Streisand to budding singers, lending their voice to the composer's famed song "Send In The Clowns."

Rock band Green Day's "American Idiot," "Enron" and "Fela!" project news broadcasts of war, conflict, corruption and politics that boldly make video more than just a small part of set design.

"More and more we are seeing it in a lot of productions on Broadway," said "Sondheim" video designer Peter Flaherty. "And the sophistication level with the use of video is definitely starting to increase on Broadway."

"Sondheim," which tells the real-life story of American composer Stephen Sondheim, blends live action on stage, including singers such as Vanessa Williams, with archival video footage and taped interviews with Sondheim himself, who at the age of 80 is only seen on screen.

The composer is Broadway's biggest "virtual character" yet, Flaherty said. He is featured center stage on a spectacular structure holding 54 monitors that artistically shift about to form different shapes that interact with the actors.

"It's an expensive design," Flaherty said, noting the days have changed since video was once seen as a cheaper alternative to using physical set design props.

"Video is performing a different role," he said.

"Sondheim's" onstage screens are run by a complicated computer system offstage, costing close to US$1 million, similar to the cost of "American Idiot's" three video projectors and 43 LCD screens.

These flash more than 600 images just in the opening title sequence, ranging from news clips of former US President George W. Bush to terrorism level alerts .