Though there is no more a responding server on winmx.com (and frontcode technologies seems to have abandonend all work on the program) there is a great community keeping winmx alive. Have a look at WinMX World.
WinMX was originally a client for Napster and OpenNap servers that could connect to many servers at the same time. In version 2.50 it was extended with a proprietary decentralized network called "WPNP". Later versions introduced decentralized chat and multi-source downloading.
WinMX is one of the largest file sharing networks, and one of the few programs which supports double-byte characters in search strings, a vital feature for languages such as Japanese. Latest versions (3.x) introduce long-awaited method of search - by hash. This network is especially good for searching for .mp3 files.
- NapMX - a tool that increases the usefulness of MP3 searching by updating OpenNap server list.