Herbstluftwm
From Gentoo Wiki
herbstluftwm is a manual tiling window manager for X11 using Xlib and Glib. Its main features can be described with:
- the layout is based on splitting frames into subframes which can be split again or can be filled with windows (similar to i3/ musca)
- tags (or workspaces or virtual desktops or …) can be added/removed at runtime. Each tag contains an own layout
- exactly one tag is viewed on each monitor. The tags are monitor independent (similar to xmonad)
- it is configured at runtime via ipc calls from herbstclient. So the configuration file is just a script which is run on startup. (similar to wmii/ musca)