Replace Your Optical Drives With a Multiboot USB
Before I found a great multi-boot tool I was using Unetbootin which is a great solution for a single bootable USB drive. But soon this tool becomes a pain when needing multiple Operating systems on a single USB drive for convenience. Since USB drives are growing in size, and with the adoption of USB 3.0 to increase the speed of USB it is a good idea to start looking into multi-boot utilities.
The solution I have found is: MultiBootISOs
This piece of software formats your usb drive to FAT32 automatically, and creates a GRUB menu for you automatically for a whole host of operating systems, live cd's, or other tools. It takes the pain and hastle out of trying to make a manual multi-boot USB and simplifies the process even further by allowing you (for some OSes) to just stick the ISO on the root directory.
Now, some of you may say that having it automatically create all the menus (even of OSes you aren't using) is inefficient. Well it is, but at least it gives you something to work off of and narrow down as you see fit later by editing the GRUB yourself if you're so inclined.
This software supports a whole host of tools like gparted, hirens boot cd, Windows 7 install disc, and many many other bootable OSes.