I always carry around with me a USB that contains bootable linux distributions for installing (centos, fedora, ubuntu, antergos, between others). But it is always annoying to test, because a machine has to be properly booted to me to be the configuration I created really boots the distribution install ISO. To ease this, since I always have kvm setup to help me with virtual machines, I discovered I could use it also to boot that precious USB stick of mine. Here is the command that will booot the USB stick:

$ sudo qemu-system-x86_64 -m 1024 -enable-kvm -hdb /dev/sdb