As of VM-Ware workstation 6.5, or VM-Ware Player 2.5 both 3d acceleration and unity mode work in windows and linux hosts. (3d acceleration support limited to 32-bit xp guests)
If you want to make your own guests, as well as edit them and so forth you will need the entire Workstation. You can download the Trial version of workstation then go to Help -> Enter Serial Number.
[NO WAREZ!!!]
I run my bot in a dual core 4.8(2.4 per core) system with 512 ram, however it works fine for me with a single 2.4core.
WoW Gliding in a VM in Vista x64
WoW Gliding in a VM under Vista x64 UNITY MODE!!! (yes, as test I also have a term from a linux guest in unity mode)