MPD is an approach to music playing that is relatively unique - instead of having one program that plays the music, controls the playlist, and pauses and plays everything, mpd uses a client-server model. The actual daemon, mpd, plays the music, and you connect to it with any number of clients to handle the playlist and controls. (I like ncmpc for handling the playlist, and mpc for quick keyboard shortcuts.)
Many mpd clients have some sort of notification system, but many, like ncmpc and mpd, don't, and I don't want to have to switch to ncmpc to see the currently playing song. So I wrote mpd-libnotify. It's a very simple program that uses libmpd and libnotify to show you the currently playing song and its artist. It's designed to be assigned to a keyboard shortcut (I use Ctrl+Alt+o), so you don't get a popup every time the song changes - only when you want it.
If you use it and like it, there are two things I ask of you: Share it with your friends, and tell me that you like it. :) (Send me an email at neal _at_ nealylitalo _dot_ net.) If you have suggestions, find bugs, or want to submit patches, I beg you to let me know. I want to make it better, and while I can't think of a whole lot of features to add to something so small, I'm sure that there are some. And I'm relatively new to the world of C, so if you have any suggestions for ways to improve my "technique", I'd be very grateful.
And feel free to let me know if you have any questions about installing it, or anything else about it.