AntiX uses a customized desktop based on IceWM, but Fluxbox is also installed (or part of the default desktop?).http://antix.mepis.org/
Yes, the 'main' version of antiX M11 has both IceWM and Fluxbox installed, but defaults to IceWM, at log-in.
version uses Fluxbox as the default WM.
All antiX versions are based on Debian's Testing branch ... and are all fast and light on resources.
The .iso file size is, well under 700Mb and can be installed on machines with under 256Mb of RAM.
Great for older hardware, processors and computers.