B4S

Description
B4S files are a proprietary, XML-based playlist format introduced by Winamp 3.0. The format appears to be deprecated, although newer versions of Winamp will load B4S playlists.

Software

 * b4s Playlist Parser - an open source project designed to export B4S to readable HTML
 * VLC Media Player supports loading of playlists in B4S format
 * Winamp

Links

 * A survey of playlist formats