FunOS
FunOS is an Ubuntu-based Linux distribution which features the JWM graphical user interface. The project is intended to be more lightweight than official Ubuntu community editions while providing the same application compatibility and hardware support.
VS
Tiny Core Linux
Tiny Core Linux is a 16 MB graphical Linux desktop. It is based on a recent Linux kernel, BusyBox, Tiny X, Fltk, and Flwm.