I noticed that, when you are changing monitor resolutions in Windows with extra monitors attached, you can select "Show desktop only on [n]" (where n is the number of your various displays).
Is it possible to write a program that will open an extra monitor (not being used by Windows, but plugged into the video card) and write image data to it (directly or through OpenGL or something)? Where would I begin looking to accomplish this?
It does not appear to be possible to draw directly to a monitor device. It may become possible to some extent with the release of Nvidia and ATI's updated drivers for VR headsets, however it seems that these are only available for Oculus Rift at the moment, with other VR headsets forthcoming.
I haven't found any mention of whether or not they intend to open this feature up to general use with any plug-and-play monitor.