Anacronia is a Multi User Dungeon (MUD), developed by Marco Fontani.
It first opened its doors on an italian server eleven years ago, in the summer of 1999.
Since then the core server has been through three major rewrites: two in C, one in C++.
This fourth rewrite, V4, is written in modern Perl, using POE and Moose.
The core server features support for MCCP, MCP, MXP and other telnet options.
The project as a whole is in its infancy, but the core server is usable.
More information on the wiki, including some benchmarks.
The code is now available in the Git repository of this project.