I just spent a looooooong time trying to use Macports' Apache2 to serve documents out of my home directory. She no work!!!11 In the absence of any meaningful log data (that I could find) to go on, I decided to just plop the whole thing into the default document root ("/opt/local/apache2/htdocs"). Voila! Immense anger!
So, does Mac OS X have something like SELinux that might prevent Apache from doing something silly, like serve files from the place I want to serve them from? I read a little about Mac OS X's MAC framework, but that didn't seem to be what I was looking for.
I was using virtual hosts, as initially configured by Macports.