trans-proxy-tor works together with PF and requires a custom
configuration. You probably want to use one of the example configurations
from %%DOCSDIR%%/filter-examples.

You will need to add:

   cloned_interfaces="lo1"
   ifconfig_lo1="127.0.0.2 up"

to /etc/rc.conf to create and configure lo1 on boot,
additionally add:

   trans_proxy_tor_enable="YES"

to start trans-proxy-tor on boot as well.

Have a look at  %%PREFIX%%/etc/rc.d/trans-proxy-tor
to see the optional variables you can use.

trans-proxy-tor must be able to access /dev/pf,
adding:

   own pf root:_trans-proxy-tor
   perm	pf 0660

in /etc/devfs.conf will take care of that. 

trans-proxy-tor's README, LICENSE and changelog were copied to
%%DOCSDIR%%.

Run:

   perldoc trans-proxy-tor

to see how to use trans-proxy-tor without the rc file.

WARNING: trans-proxy-tor's purpose can easily be defeated
by using a broken browser configuration that allows code
execution or saves and sends cookies behind the user's back.
Unfortunately most browser's do that by default.

If you aren't already using Privoxy, now would be a good time
to start. Additionally you might want to use the minor improvements
from: http://www.fabiankeil.de/sourcecode/privoxy/

Note that the broken browser configuration is just an example,
the same is true for a lot of other programs you might be using!