For creative people, mostly, music is very important. It can help to get into the mood & concentrate on a project or increase your blood pressure, send more oxygen to the brain & cause you to design/code beautiful stuff :).
pulpTunes is a free web server for iTunes which enables you to access your music collection from anywhere with a slick, Ajaxed web interface.
Music files are categorized just like iTunes, songs can be downloaded with a right-click & direct links to songs or playlists can be generated for sharing them easily with others.

pulpTunes is integrated with iTunes DJ, supports MP3 + AAC (M4A) files & can display cover arts.
For slower connections, buffer level can be easily adjusted & it works on Mac, Windows or Linux.
P.S. Although this resource is not directly design or development oriented, it is something that can be very handy for freelancers who may need to work from different locations time-by-time & for creative offices (where you can listen to music :)) to keep all music files in one place & reach easily.
Requirements: No Requirements
Compatibility: Windows, Mac & Linux
Audio Player is a tiny yet beautiful free Flash mp3 player that is used on many popular websites like Talkcrunch.
It is originally a Wordpress plugin but with the increasing popularity, the developer of the player, Martin Laine, has created a standalone version as well.

The Wordpress plugin can directly use the Wordpress media library which is great. The standalone version can be configured very easily too & they both have various features like:
- autostart
- loop
- animation
- remaining time
- volume control & more.
For a demo of the player, you can check TalkCrunch.
P.S. Audio Player is open source & source files can be found here.
Requirements: No Requirements
Compatibility: All Major Browsers
Subsonic is an open source web-based media streamer application that helps sharing your music or listening it anytime/anywhere.
It allows streaming to multiple users & can handle very large music collections.

It is compatible with every audio or video format that can stream over HTTP, like AAC and OGG. Also, Subsonic works with any network-enabled media player, such as Winamp, iTunes, XMMS, VLC, MusicMatch and Windows Media Player.
It can integrate with various web services like Last.fm, Amazon (for cover art) & more.
And, considering media files are generally huge, it supports automatic zipping/unzipping while downloading & uploading them.
Requirements: Java
jPlayer is a jQuery plugin for playing and controlling mp3 files in a webpage.
It uses a Flash file at the backstage to play the files & the player can be totally customized via XHML/CSS.

The plugin offers functions like:
- selecting the Mp3 file to be played
- play, pause, stop
- volume control
- getting the progress & more.
Thee are various demos presented like a single-file player, a playlist player or a text-based player with progress bar. To check them all, click here.
Requirements: jQuery 1.2.6+
Compatibility: All Major Browsers
Simple Flash Mp3 Player is a minimalistic player from Flabell (who also created this advanced Flash mp3 player - see WRD post).
It is built with AS3, offers a play-pause button & a draggable volume bar. Once the player is initiated, it displays the song info to be played.

There is a sound visualizer at the backend which, besides the rhythm of the music, transforms with the level of sound too.
The music to be played is set via FlashVars in the HTML code. And, the player can be customized via XML files easily.
Open Video Player Initiative is a community project by companies like Adobe, Microsoft, Akamai & for sharing player code and best practices around video player development and monetization
It comes with 2 versions: for Flash & Silverlight.

A ready-to-deploy video player and a configuration tool (for easier configurations) is provided besides the source code.
Video player can be totally customized from colors to buttons & features included.
Demos for the player can found here.
Requirements: Flash or Silverlight
Sockso is an open source music server application that lets you share the music files easily with everyone.
With a very simple setup, just running an executable file, the environment is instantly ready.

The aplication is managed from a Java GUI. User can connect through a web-based interface and:
- create playlists
- listen to the music via a Flash-based player
- download tracks, albums or playlists
- upload new music files & more.
Sockso supports MP3, OGG Vorbis, Flac, and WMA files, If needed it can re-encode output streams to save bandwidth. To see all the features of the application, click here.
Flabell is presenting a beautiful & free Flash Mp3 player that can display multiple artists & playlists.
Every aspect of the Mp3 player can be customized via XML including size, colors, speed and transition effects.

It streams the songs so there is no need to wait until the file is totally loaded. With a click, you can shuffle the songs.
And, a great feature is the share/embedding support. If enabled via XML, anyone can easily embed the player to their websites.
You can use the Flash Mp3 player directly on a website or integrate it to your Flash project by moving some ActionScript files and dragging the movieclip containing the Flash player in your Flash file.
The player comes with the source code including .Fla files, fonts & PSDs.
Requirements: No Requirements
OS FLV is an open source & embeddable flv player.
The player has a large amount of options that can be set within the embed code.

It has an API, written in PHP, that enables you to control almost anything like:
- the flv file to be played
- width, height & colors
- auto-play, auto-rewind, auto-load options
- volume, loop & more..
OS FLV also has a mambot for Joomla for an easy integration.
Requirements: PHP
AudioPlay is a simple & free Flash mp3 player with only one button.
The "play" button, once clicked, starts playing the mp3 file & turns into a "pause" button. That’s all AudioPlay does.

The images used can be easily changed by simply updating the current image files.
The settings that can be configured from a xml file:
- background color
- mp3 file name
- loop (never, x times or unlimited)
- autostart
It also supports multiple instances on the same page.
To conclude, it is an ideal player to be used as a background music player.
Requirements: No Requirements