To enable the text box on the phosphor screen saver in Fedora, the xml file at /usr/share/xscreensaver/config/phosphor.xml should look like below:
<?xml version="1.0" encoding="ISO-8859-1"?>
<screensaver name="phosphor" _label="Phosphor">
<command arg="-root"/>
<number id="delay" type="slider" arg="-delay %"
_label="Speed" _low-label="Slow" _high-label="Fast"
low="0" high="80000" default="50000"
convert="invert"/>
<number id="scale" type="spinbutton" arg="-scale %"
_label="Font Scale" low="1" high="100" default="6"/>
<number id="fade" type="slider" arg="-ticks %"
_label="Fade" _low-label="Slow" _high-label="Fast"
low="1" high="100" default="20"
convert="invert"/>
<select id="mode">
<option id="dumb" _label="Text Only" arg-set="-pipe"/>
<option id="pty" _label="Terminal Emulation"/>
</select>
<file id="program" _label="Text Program" arg="-program %"/>
<xscreensaver-text />
<_description>
Draws a simulation of an old terminal, with large pixels and
long-sustain phosphor. This program is also a fully-functional VT100
emulator!
Written by Jamie Zawinski; 1999.
</_description>
</screensaver>
Also don't forget to use an OUTPUT program to print your text file, something such as 'cat'! ie: cat /home/username/myCoolTextfile.txt