-Note: this program doesn't work as a screen saver on all systems,
-because it doesn't communicate with xscreensaver properly. It happens
-to work with some window managers, but not with others, so your
-mileage may vary.
+Note: SSystem does not work as a screen saver on all systems, because
+it doesn't communicate with xscreensaver properly. It happens to work
+with some window managers, but not with others, so your mileage may
+vary.
+
+SSystem was once available at <http://www1.las.es/~amil/ssystem/>,
+but is now gone. You may still be able to find copies elsewhere.
+
+SSystem has since evolved into Celestia, found at
+<http://www.shatters.net/celestia/>. Sadly, Celestia does not work
+with xscreensaver at all. You are encouraged to nag the authors into
+adding xscreensaver support!