As if the Linux world did not have enough CD players, I wrote one myself. I wrote the CD player by finally understanding how to use ioctl() and how to understand the information in the linux/cdrom.h file.
WiredX is an X Window System server written in pure Java(tm). WiredX enables you to access UNIX/X applications from all web browsers with Java Plug-in. WiredX accepts X window protocols directly, so you don't need any proxy program. Its "beta" and "Lite" versions are available for non-commercial/commercial use without fee.
Sticky Notes provides a way to have little sticky notes on your desktop. It is similar to knotes but does not require KDE and features better configurability.
RaVeR (See the Music!) is a sound animation program. It renders full screen 3D animations in synchronization of music or any kind of sound at realtime! It is open source, free, works in Linux using ALSA and OpenGL. (old SDL and SVGALib versions avail.)