What it does.

• Serves MP3 audio to multiple listeners using the de-facto "ShoutCast" protocol over standard TCP sockets. The number of simultaneous listeners is primarily limited only by network bandwidth.
• Serves multiple "radio stations" on different ports simultaneously.
• Supports ordered or shuffle play of audio tracks.
• Allows MP3 files to be added and removed from a station on the fly, without restarting the server.
• Can easily be extended (by writing new Java classes) to acquire MP3 data from any source, and order the playlist in any sequence.
• Generates customizable HTML files giving info on the current track and recent tracks; these can be served via any HTTP server (such as Apple's Web Sharing) on the same computer.

What it doesn't do (yet).

It's early days. Compared to mature servers like ShoutCast and IceCast, RadioStation isn't very fancy ... yet. It doesn't do things like:

• Any kind of GUI-based setup and administration, whether web-based or via a local app. (The absence of this really pains my heart since I implement AWT for my day job, and I promise it's a high priority! I don't like editing cryptic configuration files any better than you do.)
• Cross-fading between tracks -- this requires decoding the tracks, mixing the audio, and re-encoding, and RadioStation doesn't do any encoding. It just shovels pre-encoded data from your hard disk to the network. (I don't plan on adding MP3 encoding myself; I don't know if Java is ready for it yet. Maybe someone else will take this as a challenge.)
• Streaming audio in other formats like AIFF or WAV -- again, this would require doing MP3 encoding.
• Matching the bit-rates of all files -- once again, this requires re-encoding.
• Support variable-bit-rate files. The bandwidth-management code assumes the whole file has the same bitrate. But most MP3 players don't support VBR streams anyway.