I have a new Friday project, it's an mp3 player plug-in for NetBeans. It's still in a very early stage but the plans are big :) I would like to create a nice Winamp-like UI with basic mp3 playback features. I am also thinking about integrating RSS so that it can be used to subscribe to podcasts and play them.
So far I have a very simple player which can already be used to play both mp3 files and can handle playlists. It's pre-alpha quality so don't be surprised if you get any exceptions... and the GUI is still ugly, it will be nicer once I'll create some graphics.
The very first version of mp3 player for NetBeans
You can get the nbms here
and the sources here
. I will create a project website for it soon.