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.
Super Grub2 Disk is a live CD that helps the user to boot into almost any operating system even if the system cannot boot into it by normal means. This allows a user to boot into an installed operating system if their GRUB installation has been overwritten, erased or otherwise corrupted. Super Grub2 Disk can detect installed operating systems and provide a boot menu which allows the user to boot into their desired operating system. Super Grub2 Disk is not an operating system itself, but a live boot loader which can be run from a CD or USB thumb drive.