Wmctrl is a command line tool to interact with an EWMH/NetWM compatible X Window Manager (examples include Enlightenment, icewm, kwin, metacity, and sawfish).

Wmctrl provides command line access to almost all the features defined in the EWMH specification. For example it can maximize windows, make them sticky, set them to be always on top. It can switch and resize desktops and perform many other useful operations.