Notion is a tiling tabbed window manager for X. This means the screen can be freely divided into tiles that contain the client windows. Multiple client windows can occupy the same tile; in that case they will be tabbed, much like browser tabs. This way, windows will not overlap and it becomes easier to manage your screen real estate. Its functionality can be configured and even extended with Lua scripts. Various scripts are available, such as for NetWM features and multihead support.
WMFS (Window Manager From Scratch) is a lightweight and highly configurable tiling window manager for X. It can be configured with a configuration file (made with LibConfuse), supports Xft (Freetype) fonts and is compliant with the Extended Window Manager Hints (EWMH) specifications.
MIcroscopic Window Manager (MIWM) is a fast, small, minimalist, and extremely reliable window manager. It is designed to do the job very simply and unobtrusively, without constraining power users. It features optional auto-tiling, desktop cleanup, a user-defined root menu, optional previewing of hidden windows, variable numbers of virtual desktops, and configurable window behavior. It includes a simple, very effective memory management utility for leak detection.
IceWM Control Panel is a full-featured, GTK-based control panel for IceWM. It features an IceWM theme designer, Ice Sound Manager (for sound events), IcePref2, and tools to manage desktop wallpaper, cursors, keys, window options, and more. IceWM Control Panel has a familiar, Windows-like Control Panel user interface.
IcePref2 is an updated, overhauled, improved, and perfected version of the original IcePref (which was abandoned by the original author). This new version includes many new features and bugfixes, and is a sub-project of the IceWM Control Panel project. It is optimized for IceWM 1.2.2 and better.