xbmsd is a file sharing daemon that uses the Xbox Media Streaming Protocol (XBMSP) supported by the Xbox Media Center. It also supports the XBMSP Server Discovery Protocol (XBSDP). Its main features are mapping files to arbitrary local files or HTTP files/streams, support for filetype-specific, "synthetic" mplayer configuration files, and support for filtering files with arbitrary programs, which can, for example, re-encode media files on the fly.
xcplay is an ncurses interface to XMMS. The UI is a clone of cplay, but using XMMS as a backend instead of console players, running either as a GUI-stripped daemon or on a virtual X server (Xvfb). Advantages over cplay include seeking for many more formats, detachment, unlimited instances, and console player independence.