From PC-BSD Wiki
is a powerful and highly configurable desktop window manager for the X Window system. It supports any number of virtual desktops, each divided into multiple pages. It also supports side title bars, including vertical text.
When you install FVWM on PC-BSD®, it also installs. Both window managers will be added to the login menu. Figure 6.4a shows the default PC-BSD® desktop if you select FVWM from the login menu. The application menu was opened by clicking the mouse anywhere on the desktop. Figure 6.4b shows the default PC-BSD® desktop if you select FVWM-Crystal from the login menu. To open an xterm in FVWM-Crystal, right-click any area of the desktop.
Theprovides information about configuring FVWM.