Check this out... (requires Java)
Back in 1994 I was doing a few first steps in X Window Programming,
and I ported this effect from my Amiga to X, mostly as an exercise,
after a friend got me the sources for the Amiga program.
As I used xlock(more) then, I added it, and it became part of the
official release. It went over to xscreensaver and whatnot, and seeing
this now after 13 years makes me a bit nostalgic.
(I think I'll try not to think about the platform implications,
going from X on a Sun to a Java plugin running inside a webbrowser
on a *cough* Linux system. Who's got a Flash version of this? :-)
To get back on-topic, of course you can run this without
Java and a webbrowser on NetBSD, too:
$ cd /usr/pkgsrc/*/xlockmore
$ make install
$ xlock -mode galaxy
[Tags: galaxy, hubertf, xgalaxy, xlockmore]