MultiBoot USB
This is a collection of GRUB scripts that allows to create a bootable pendrive (USB dongle, flash stick) supporting a number of different OS images. Simply copy ISO files under `/iso-imgs`. Both UEFI and Legacy BIOS boot modes can be enabled simultaneously.
Slax is a Slackware-based bootable CD containing a Linux operating system, designed with a modular approach. Despite its small size, Slax provides a wide collection of pre-installed software for daily use, including a well-organised graphical user interface and useful recovery tools for system administrators.