Acez Jukebox
Player and mixer software intended for consumer and professional use.
http://www.acez.com/mp3.htm

Tiny ArtOfNoise Player
Small utility used to replay Amiga made "Art Of Noise" or "Chorus" songs on Atari Falcon computers.
http://tap.atari.org/

Discotheque Sound System
MP3 DJ mixing software with automatic beat-matching, recording, dual player, cue support, and crossfaders.
http://www.myxoft.com/

TitleTrack Jukebox
Macintosh program for controlling the Sony line of 5 to 400 disc capacity music CD Changers.
http://www.titletrack.com/

XMPlay using BASS audio library
Windows music player supporting MP3 and many tracker formats.
http://www.un4seen.com

Oozic
Player that also gives dynamic visual expression to music by displaying graphics.
http://www.oozic.com

Synaesthesia
CD player that also represents music graphically in real time as changing field of fog and glowing lines.
http://yoyo.cc.monash.edu.au/~pfh/synaesthesia.html

DFX Power Technology
Plug-ins to improve the sound quality of many players.
http://www.fxsound.com/

XMCD - Motif CD Player
Free CD audio player for UNIX and OpenVMS that can query the CDDB over the Internet.
http://www.ibiblio.org/tkan/xmcd/

Sound Cue System
Designed for running sound cues and sound effects for live theatre productions.
http://www.soundcuesystem.com

Interactive Groove
For Jamlet files, linear or kaleidoscopic. Kaleidascopic plays the music differently each time and can play continuously.
http://www.interactivegroove.com

Foobar2000
Multi-format audio player for Windows, low resource usage, features include playback from archives.
http://www.foobar2000.org/

@MAX Tray Player
Taskbar integrated player allows for easy access to all media files on the computer.
http://www.atmaxsoft.com

JukeANator Digital Jukebox
A Java application that plays MP3, WMA or iTunes songs and has commercial and non-commercial versions.
http://www.jukeanator.com

Fun SoundPlayer Maker
Creates Flash sound players for website background music.
http://www.funsoundplayer.com/

Silverjuke
Jukebox with album generation, kiosk-mode, modern and traditional skins.
http://www.silverjuke.net

Blogamp
A web audio player component for bloggers that can be embedded, posted, or launched in a pop-up window.
http://www.blogamp.com

CDizz
Freeware player that adds multimedia content to any audio CD.
http://www.cdizz.com

AudioPlayer
Windows based, freeware open source media file player written in C. Formats covered include MP3, WMA, and MIDI.
http://audioplayer.sourceforge.net

Dotweb MP3 Web Player
A PHP audio player for internet radio and audio such as MP3, WAV, M3U, WMA.
http://dotweb.xhost.ro

SoundSpectrum
Music visualization software in the form of media player plug-ins and standalone products. G-Force, WhiteCap, Darkroom. Free trial versions.
http://www.soundspectrum.com

Plopbox
Old school including Amiga, Atari, and C64 tunes played directly from the site. Web radio options, old school community.
http://www.plopbox.net

Winamp
Provides free Winamp player download, community skins and plug-ins, free on-demand audio, video/film, and games.
http://winamp.com/