Like I said, it was a real pain in the ass to set up. IIRC, once you got past all the conflicting hardware, it then had both sets of drivers and just disabled the ones that weren't there. I could remember wrong, though. Also, that probably works much less well with XP now that it enforces that hardware change restriction.

At the very least you might be able to set up a partition-based data filesystem that could be shared between separate VMWare and real Windows installations.