I used some old documentation and some reverse engineering to create a PHP-based AOL instant messenger script for the original TOC protocol. When I showed it to Andrew Heebner (formerly of evilwalrus.com), he added some TOC2 (a revision of the original TOC protocol) functionality and lots of documentation. He called it TAC and we agreed on making it available on the internet under the Artistic License. It was created for beta versions of PHP5.
I also made some of the original TOC1-only script available, as a PHP4 class named AOL_TOC, which is copyrighted by me. It requires PEAR and it's only been tried with PEAR < 1.4.0.