Felidae is a collection of modules for Fvwm. FvwmStorage lets you define variables, load and store them from/to files, and execute any fvwm command using them. It is especially useful to interactively change the fvwm configuration. FvwmWallpaper lets you change your X wallpaper from within Fvwm. It tries to find the best way to display your picture and resizes it if necessary. FvwmXMMS lets you control XMMS by sending commands to this module. FvwmOsd lets you display an on-screen display on your X display. FvwmOsd is organized in different "channels", each of which you can configure and use independently of the others.
FVWM-Crystal aims to create an easy to use, pretty, and powerful desktop environment for Linux or other Unix-like operating systems. It uses following programs: FVWM as a window manager and "main core", ROX-Filer as file manager (manages icons on the desktop), xterm, aterm, mrxvt, or urxvt as terminal emulators, MPD or XMMS as music players, and several other tools for different functions, like setting a wallpaper or making screen shots.