VMac or Virtual Macintosh is a new project by a group of university students to try to emualte a Mac on the PC. The principle in which the emulator works is very much the same as the way UAE works. In fact most of the code is taken from UAE source.
It uses a ROM taken from a Mac like UAE and has the same trouble as UAE has. It cant read Mac disks. Well as far as I am aware. I have just put a Mac DD Disk into my PC and "Drive a: not accessable". But unlike Amiga disks, I bet a piece of software has been written to allow Mac disks to be read by a PC.

As I and most people are VMac and Mac virgins I dont know too much about VMac or the Mac for that matter; all I do know is that there will be a working copy (when available) on my PC!

Official VMAC Site  http://leb.net/vmac/
Another VMac Site http://mluwis17.wiwi.uni-halle.de/~tom/vmac.html
Emulation.net - Full of emulator links (Mainly Mac)http://www.emulation.net

Other Mac Emulators:-

Executor - A `Patched` emulator, which tries not to use the Mac ROM like vMac, but to emulate the Mac's OS. This is not a good way to go about it in my opinion. It only runs 40% of applications in my experience and also it is commercial and sells for $249!! (But no ROM's or OS is needed).

Gemulator 97 - Is actually an Atari ST emulator. But it has an Atari ST Mac emulator built in! So you run Gemulator on a PC, which emulates an ST which emulates a Mac! Havn't tried it as you need ST TOS ROM's which I don't have lying around - And again it is commercial but is only about $100!

Shapeshifter 3.7 - A Mac emulator for the Amiga. Ihave tried running it on UAE and havn't had much luck so can't really comment but people that have got it going say it runs and performs like a real Mac - But they have probably got 200MHz MMX's!!

More vMac information will appear here as soon as I get it. If you want to contact the vMac team, the main author of vMac, is Philip Cummins who will be pleased to help. There is also a Discussion board (not disimilar to UAE's) which you can link to from the vMac main site.