After juggling multiple concurrent non-compatible versions of a product I'm working with, I finally broke down and did something I had been thinking of since the PDC days - setting up an image server. While many bloggers went the route of buying a new box for Longhorn, it wouldn't solve my problem of needed multiple exotic configurations  - Win2003 with Infopath, SPS and Project Server one day,  Win2K with Infopath and Biztalk the next, and a little Longhorn in my spare time.  And my desk at home already has 4 computers lurking on/under/around it, which is the max I can squeeze in without breaking the laws of physics. 

One of my boxes is a Dell PowerEdge server which is currently a dedicated file/print/mail server. [I take my data seriously, it gets its own box.]  I installed VPC on that, beefed it up with an extra 1GB of ram (~200$, the good ECC stuff) and a 250GB disk (~120$). Now I'm in the process of setting up the images, and then- Longhorn, here I come!  And for a bit over $300, it wasn't that painful either...