Another post looked at a couple of different techniques for showing/hiding files on a Mac OS X machine. Although it wasn't really spelled out in the summary the post focussed on the best way to first show a hidden file/folder (like an .htaccess file - typically any file that starts with a period will be hidden in the Mac OS X Finder) and then hide it again.
At first glance it might seem that the technique could be used to hide a file that would normally be visible, as a way to secure files you did not want other people to see.
That is actually a very different thing. System files are hidden for convenience, to avoid cluttering up the interface. The machine might need them but the users certainly don't so why show them? It's better to just make them disappear by default.
But that is very different from really securing your files. "Security Through Obscurity" is not security, and an attempt to secure files by making them hidden will fail quickly and almost immediately in the hands of even an intermediate Mac user. All the user has to do is use one of the tricks from the last post, or search using the OS X Finder with the "File Visibility" option set to "Visible or Invisible".
If you have files on your Mac that you want to hide or secure, and they're worth the inconvenience of the methods described in the other post, then they are definitely worth securing properly. This post looks at a very easy way to properly hide, secure and encrypt files on your Mac.