Comment by userbinator

The IRC protocol is both text-based and simple enough that you can use something like netcat as a client (and I have, many times.) The line-based format fits IM perfectly, and the overhead of the protocol is a tiny fraction of the bloated proprietary ones that have filled this use-case today (except MSNP, which in its earlier versions was also delightfully simple and easy to write a client for, but definitely beyond the threshold of being usable "raw".)