Bus riders in China need not while away the miles gazing out the window. Instead, they can turn their attention to VisionChina Media. The company operates an advertising network that consists of more than 120,000 digital television displays, mainly on buses and subways, in about 20 major Chinese cities. The displays receive mobile digital broadcasts from local TV stations of real-time content -- such as news, stock quotes, weather and traffic updates, sports highlights, public interest messages, and other entertainment programming -- sprinkled with paid advertisements. The vast majority of the company's revenue comes from the sale of ad time; about 1,000 companies have advertised on the network.