vCenter Client for Mac/Linux!? No, not completely, but a most useful tool.
I was lucky enough to play w/ some early builds that Steve put together and now it's finally a 1.0 product. I highly recommend downloading and playing with it in the very least. It is a free download.
The one bug that I remember reporting, that doesn't appear to have been fixed yet though is that the client doesn't understand folders in the hosts & clusters view. So if you have clusters/hosts in folders, it will not enumerate those in the client. So it's rather useless to me currently, but should work fine for most people.
You can read more about it here: