Bochs lets a computer emulate an x86 architecture, and for instance, run Windows on a Mac, much like VPC, although slower. I know (or believe?) that on Windows, one can use Bochs to run a second OS under a virtual machine within a computer that is already running on the x86 architecture with more things native and less emulated, allowing one, for instance, to run Linux in a VM environment within Windows, or vice versa. Is there anything similar that would let one run Panther inside Tiger? I am starting to wonder if it might be an option for apps like SPSS which have misguided developers who will update them God-knows-when or never.... I thought I saw something like this once as an option to run YellowDog or somesuch within OS X. Does it exist? I'd think such a VM might not be too painfully slow, and might be good enough to run a legacy app or two? Or am I being too optimistic?