Yes, I remember a display like that was made for the Mac some time ago as well.
Does anyone know if galleries are starting to use LCD panels to display 'slideshows' of images? Seems like a way to make a gallery display a bit more dynamic.
Back in the 1980's, Wang issued computers for document processing where the monitor could be switched from horizontal to vertical, since many users found it more convenient to show a portrait-mode document on screen efficiently. I haven't seen anything like that recently, but I don't imagine it's a monitor issue anyway - seems more like a video driver issue. If you find one, and you can have two monitors operating at the same time, you can send the landscape-mode images to the landscape monitor, and the portrait-mode images to the portrait monitor. You wouldn't want to be turning the monitor all the time.