The 6.03 version of XScreenSaver for Mac is provided as a free download on our software library. This free Mac app was originally designed by Jamie Zawinski. The application lies within Theming Tools, more precisely Screensavers. The current installation package available for download requires 56.1 MB of hard disk space.
From the developer:
XScreenSaver is a collection of several hundred screen savers. This is a Mac port of the standard screen saver collection shipped on most Linux and Unix systems.
You may want to check out more software for Mac, such as Substrate, which might be similar to XScreenSaver.