4MLinux Core
http://linux.softpedia.com/get/System/Operating-Systems/Linux-Distributions/4MLinux-Core-61479.shtml#download

4MLinux Core is an open source distribution of Linux, a special edition of the 4MLinux operating system designed to provide users with a very minimal environment for creating their very own Linux distributions from scratch.

This is the core edition of 4MLinux, on which all the other 4MLinux flavors are based, including 4MLinux Main Edition, 4MLinux Game Edition, 4MLinux Media Edition, 4MLinux Multiboot Edition, 4MLinux Rescue Edition, 4MLinux Server Edition, and 4MLinux Allinone Edition.

It is used to create all other 4MLinux editions

With this distribution it’s possible to create any Linux-based operating system that can be used as a system rescue CD, for playing multimedia files and games, a capable Web or FTP server using the inetd daemon, or a standard workstation.