There's been a lot of talk recently about our new "Windows Server 2008 Workstation" (Windows Server 2008 with the Desktop Experience features switched on - plus a bunch of hacks). There's been suggestions that it out-performs Vista - I'm not going to enter that can of worms, but I can see a need to run a server operating system as your main OS.
Hyper-V seems to be out-performing every other virtualisation product out there and it's "free". But to get it, you have to run Windows Server 2008. You're not going to be able to run the Server Core installation on your main laptop (because of the small requirement for a UI), but the full install does make sense. But now you want all the Vista "bells and whistles"? You could spend a good long while trawling through various discussions all explaining how to enable certain "features" (Aero, SuperFetch, Audio, Wireless Networking, etc) or you could look at this great little tool I stumbled across today: Windows Server 2008 Workstation Converter
I haven't tried it (yet), but it looks to be the "bee's knees".
One word of warning - if you're going to use Hyper-V you'll lose the ability to enter Standby and Hibernation.