gnome-control-center/capplets/screensaver/screensavers/munch.xml

<?xml version="1.0" encoding="ISO-8859-1"?>

<screensaver name="munch" _label="Munch">

    <command arg="-root"/>

    <number _label="Speed of Motion." _low-label="Faster" id="delay"
            type="slider" default="2" arg="-delay %" low="1"
            _high-label="Slower" high="500000"/>

    <boolean _label="Use XOR drawing function." arg-unset="-no-xor"
             id="xor" arg-set="-xor"/>

    <boolean _label="Draw square at weird starting points."
             arg-unset="-no-shift" id="shift" arg-set="-shift"/>

    <boolean _label="Display screensaver in monochrome." arg-unset=""
             id="monochrome" test="mono" arg-set="-mono"/>

    <_description>
        DATAI 2							      
        ADDB 1,2						      
        ROTC 2,-22						      
        XOR 1,2							      
        JRST .-4						      
								      
As reported by HAKMEM, in 1962, Jackson Wright wrote the above PDP-1 code.  That code still lives on in this screenhack, some 35 years later.  The number of lines of enclosing code has increased substantially, however.  This version is by Tim Showalter.</_description>
</screensaver>