VMWare Fusion 3 Performance Tuning

"Allocate 2 CPUs and at least 2GB RAM to the VM. Make sure Windows has an adequate page file; I recommend 2GB minimum.

If you can, set your MacBook to boot using the 64-bit kernel and extensions. By default, most current Macs still boot with the 32-bit kernel. Google finds much info about this, including this page:
http://newchaos.posterous.com/64-bit-on-snow-leopard-macos-x-106x

Combined with romant's prior advice, I saw a noticeable improvement, especially in terms of reduced typing lag in Visual Studio 2008. We'll see if this better performance continues tomorrow at work..."

"If you don’t need it, disable Windows Index search and Restore points. Hard drive is probably the worst slowdown. Try to tweak your windows as if it were a real box you have with limited hardware. Removing unnecessary services also helps a lot and keeps windows more quiet.

There are various guides around the net (google is your friend) on what services you can “safely” disable to get a performance boost.

Also search on Stack Overflow for a few Visual Studio tweaks (there are a few interesting threads about it there); it all helps a lot. If you have an external FW800 or faster drive, moving the VM there also helps balancing the load between the two slowest pieces of hardware. Unless, of course, you have a SSD :)"