As I reported few weeks ago a special VMware image is circulating on the Net: is the experimental Apple MacOS x86, hacked to bypass the hardware check Cupertino guys created to avoid installations on unauthorized x86 machines.
The image really exists (actually called tiger-x86.tar.bz2) but there are alternatives to setup a MacOS 10.4.1 inside VMware: at the xplodenet.com site you’ll find 4 simple guides to achieve the task.
A blogger posted some screenshots (I’m assuming are not fake).