Archiso

"Archiso is a small set of bash scripts that is capable of building fully functional Arch Linux based live CD/DVD and USB images. It is a very generic tool, so it could potentially be used to generate anything from rescue systems, to install disks, to special interest live CD/DVD/USB systems, and who knows what else. Simply put, if it involves Arch on a shiny coaster, it can do it. The heart and soul of Archiso is mkarchiso. All of its options are documented in its usage output, so its direct usage wont be covered here. Instead, this wiki article will act as a guide for rolling your own live mediums in no time!

Due to recent changes, Archiso will now automatically create ISO images that are also USB images! Separate CD/USB targets are therefore no longer necessary."

https://wiki.archlinux.org/index.php/Archiso