And indeed, lo and behold, it works. Quite well, actually. Hhere is what I did:
vmware-install.pl
All defaults were sane on my Kubuntu desktop, no complaints.
I then tried to be cute and started two Quantian instances (which can be done if you copy the .vmx file to a new file), started both in kernel 2.4 and tried openMosix, It didn't start immediately, presumably because the test for /proc/hpc got tricked by the /proc filesystem of the non-openMosix host. A quick 'mkdir mfs; /etc/init.d/openmosix start' later, things started to roll. However, while the two machines 'saw' each other, no actual job sharing seemed to occur. They also did not 'see' the laptop running outside the hosted VMware setting even though all machines were on the same 192.168.1. subnet. Maybe a simple configuration issue, maybe not.
All in all, a pleasant surprise that I was able to set all this up in a couple of minutes.
Update: Fixed URL for the Quantian.vmx file.