Remember the advertising-laden skyscrapers from Blade Runner? Mitsubishi's now got the tech to do it: its Diamond Vision screen uses individual 4-inch square OLED panels that can scale to an unlimited size. Check out the 155-incher on show at CEATEC.
That's definitely the biggest OLED screen I've heard of. Of course, the individual panels are a bit of a cheat—and mean you only see a red, green and blue matrix until you're at least two feet away—but Mitsubishi imagines the tech being curved around buildings, trains and buses in Japan.
OLED screens are capable of much higher resolutions than regular stadium-style LED displays, but have two fatal flaws. They're super expensive, and OLED degrades. The expected life of an OLED panel is only about 20,000 hours (roughly 2.5 years). Gorgeous as they are, that's why you're not reading this on an OLED screen right now. [OLED-Display.Net and Network World]