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.
Parted Magic is a small live CD/USB/PXE with its elemental purpose being to partition hard drives. Although GParted and Parted are the main programs, the CD/USB also offers other applications, such as Partition Image, TestDisk, fdisk, sfdisk, dd, ddrescue, etc. In August 2013 the distribution became a commercial product and is no longer available as a free download.