MultiBoot USB
This is a project that contains a collection of GRUB files and scripts that will allow you to create a pendrive capable of booting different ISO files.
SliTaz GNU/Linux is a mini distribution and live CD designed to run speedily on hardware with 256 MB of RAM. SliTaz uses BusyBox, a recent Linux kernel and GNU software. It boots with Syslinux and provides more than 200 Linux commands, the lighttpd web server, SQLite database, rescue tools, IRC client, SSH client and server powered by Dropbear, X window system, JWM (Joe’s Window Manager), gFTP, Geany IDE, Mozilla Firefox, AlsaPlayer, GParted, a sound file editor and more. The SliTaz ISO image fits on a less than 30 MB media and takes just 80 MB of hard disk space.