This is a tool to cheat an X11 server to believe that there are more monitors than there actually are. It hooks into libXRandR and libXinerama and replaces certain, configurable monitor configurations with multiple virtual monitors. A tool that comes with this package can be used to configure how monitors are split.

This tool used to only work with XRandR, but I found it useful to add Xinerama emulation. It can be readily removed if it isn't needed though. Note that this tool right now only works for legacy Xlib applications. Applications using xcb will not work.