MPX is a multi-input extension for the X Window System. It would allow, if hardware permits for touchscreen input, for multi-touch access of the GUI. For mice, it could allow up to 18 working mouse pointers in one instance. MPX won't be built into the currently upcoming X.Org release, X11R7.4. Instead, while it was already merged in March 2008, it will be packaged as part of X11R7.5.