Thanks Tim and Terry.  Stackless Python sounds interesting.  It's nice to know that others had the same idea I did, although I tend to shy away from exotic variants since they tend to be less well-supported.  Any chance that CPython will go stackless at some point in the future?

By the way, I saw that I can increase the process stack limit from within a Python app:

    resource.setrlimit(resource.RLIMIT_STACK, (resource.RLIM_INFINITY,
                                               resource.RLIM_INFINITY))

I tried it, and it works (on my Linux system), but of course is unavailable on Windows systems.