SliTaz

SliTaz is a free micro GNU/Linux distro using BusyBox, a Linux kernel, and GNU free software. The goal of SliTaz is to have a GNU/Linux distro working all in memory (RAM), installable on hard disk, with a good support for French language, oriented web and PC recycling. SliTaz boot with Syslinux, provide more than 200 Linux commands, Lighttpd web server, SQLite database, rescue tools, an IRC client, SSH client/server powered by Dropbear, X window system, JWM (Joe's Window Manager), gFTP, Geany IDE, Mozilla Firefox, Alsaplayer, and much more. The SliTaz ISO image will always fit on less than 30 MB, trying to give you a reasonable selection of software.
 * Official English site