The "Creating a POPfile Startup Item for Mac OS X" section on this page:
http://getpopfile.org/docs/howtos:macosx#creating_a_popfile_startup_item_for_mac_os_x

has some minor typos/errors.

In section 7, this line:

sudo chown -R root.admin popfile

should have a colon not a dot between root and admin, like so:

sudo chown -R root:admin popfile
------------------^

Secondly, both that line and first chmod line further down use "popfile" uncapitalized, instead of the "POPfile" capitalization used in the previous sections. This difference won't matter if you're using a non-case-sensitive filesystem, but needs correcting to work for those of us who aren't.

(Note: all comments relative to an older 10.6.8 system)