1. In a computer system running an M-bit preemptive multi-tasking operating system, a method for running multiple N-bit cooperative multi-tasking operating system applications, where N is less than M, the method comprising: creating a separate virtual machine that emulates the N-bit cooperative multi-tasking operating system environment for each such multiple N-bit cooperative multi-tasking operating system application; and running each such separate virtual machine within a separate M-bit preemptive multi-tasking process.