Software > Web servers >
Web server software.
I used it extensively from probably 2002, maybe earlier, for pre-PHP 4 MediaWiki experimentation. It's a fucking nightmare. Looking at some references, it might be around Apache 1.3
A peer-to-peer file sharing program which instead lets you subscribe to people to get files in a "sink-discovery" system.
Had a lot of potential, and is significantly better than other systems and programs. Was stillborn.