Privoxy v3.0.6, as installed through the Tor & Privoxy & Vidalia bundle (version 0.1.2.17), does not launch automatically on start-up. A workaround is to create a file named org.privoxy.plist in /Library/LaunchDaemons that contains the following code:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
<key>Label</key>
<string>org.privoxy</string>
<key>Program</key>
<string>/Library/Privoxy/StartPrivoxy.command</string>
<key>RunAtLoad</key>
<true/>
</dict>
</plist>$ sudo chown root:wheel /Library/LaunchDaemons/org.privoxy.plist
$ sudo chmod 700 /Library/LaunchDaemons/org.privoxy.plist
This is hardly ideal; I believe a better solution would set launchd to listen to port 8118 and then launch privoxy on demand.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20071016144328111