What are some alternatives?
When comparing bspwm and Fluxbox, you can also consider the following products
i3 - A dynamic tiling window manager designed for X11, inspired by wmii, and written in C.
IceWM - icewm home page . Bug Tracking. If you have a patch, a bug report or a feature request to submit, please do so at the icewm project page at SourceForge.
dwm - dwm is a dynamic window manager for X. It manages windows in tiled, monocle and floating layouts. All of the layouts can be applied dynamically, optimising the environment for the application in use and the task performed.
awesome - A dynamic window manager for the X Window System developed in the C and Lua programming languages.
herbstluftwm - herbstluftwm is a manual tiling window manager for X11 using Xlib and Glib.
Xmonad - xmonad is a dynamically tiling X11 window manager that is written and configured in Haskell.