Amongst all the hype about Hyper-V and VMWare’s ESXi 3.5, I think a lot of people tend to forget about the other offerings out there. Hyper-V is essentially free, available for a very low cost if you buy the Windows 2008 version with it on it. Frankly, I don’t know why you would buy the version without it. I certainly can’t think of a good reason. Also VMWare ESXi 3.5 is free now due to the recent announcement from VMWare. Based on this, it’s quick to get caught up in the virtualization fun since you can acquire either product quite readily.
However, there is another alternative. You can try out Citrix XenServer Express Edition from Citrix. This is due to the latest acquisition by Citrix. The Express Edition version allows you to run 4 virtual machines for free. You can get it at this link here.