Lol! I can run DOS using vpc. As for BeOS I know nothing. Definition I could find:
BeOS: An operating system developed by Be, Inc. that runs on the PowerPC platform and Intel x86 processors. Despite being smaller than other modern operating systems, such as the Mac OS and Windows, BeOS nevertheless sports a modern graphical user interface (GUI), preemptive multitasking, multithreading, and built-in support for symmetric multiprocessing (SMP).
PowerPC Platform: a computer hardware specification that allows a computer to run multiple operating systems. PPCP was developed jointly by Apple, IBM, and Motorola ... A computer that meets the PPCP standard allows you to select an application without regard to the underlying operating system. A PPCP computer can run any Mac, PC, or UNIX-based operating system without the usual modifications required to fit an operating system to a platform.