Sliver is a Server daemon and a client program that reads log files, and accept remote commands through the TOC protocol using Net::Aim and encryption. Sliver is written mostly using Perl, but this may change.
Internet Relay Jabber (or IRJ) is a Jabber client for IRC. It's useful if you like IRC, but your friends use another IM service. It is written in Perl and uses Net::Jabber and Net::IRC. (This project is no longer under active development)