You can get a flavor for the front-end from this screenshot of the Apache management panel. As you can see, it can customize nearly every piece of the Apache configuration file.
I downloaded and installed webmin just to see if it would work. It supports a huge number of UNIX variants, including freeBSD and Mac OS X Server. I told it I had OS X Server, and found that some modules worked, and some did not. The important ones (the scheduler, Apache configuration, system log browsing) all seemed to work fine. I had to edit a couple paths in the webmin settings, but this was easily done via the web browser.
One note of caution - this is a large package, consisting of over 4,000 files and 17+mb of disk space. It comes with a very nice installer and uninstaller, both of which worked as advertised ... with one exception. Make sure you install it on a volume with no spaces in the volume name, otherwise the installer will complain and fail.
Read the rest if you'd like to see how to install it.
Installing webmin is quite simple; there are instructions on their site, but the basics are to decompress the package, and then run the setup program as root. That's about all it requires.
I had to manually edit the path for Apache files in order to make that module work. You can access this in the webmin configuration panel of the program itself. There are a huge number of UNIX variants to pick from as the base OS, and they can be changed post-install via the web browser. I didn't experiment with any of the BSD options to see how well they might work.
Overall, it's a quite impressive package ... as with anything this powerful, however, the potential to greatly damage your system is probably equally impressive. Use it with caution!

