[arch-general] Virtualization accross hardware border

Dear list, if I understand the offering of Amazons cloud service correctly, there, you can install an OS, say arch, on a virtualized machine and scale CPU, RAM, etc. freely up and down just as you need it. While I can to this using e.g. KVM+qemu on a single machine, I want to be able to bind together a bunch of machines such that they appear as a single big machine. Is there a way to do this? I my question clear enought to be answered? Thanks, Wolfgang