Hyper-V Templates - the free method
Microsoft obviously wants you to buy System Centre Virtual Machine Manager - SCVMM - really rolls off the tongue. For a simple test environment, however, this simply isn't necessary and it's relatively straightforward to create templated VMS just using the built-in importing and exporting in Hyper-V Manager. Combined with the fact that Hyper-V standalone is free, this is a total pro-bono solution!
This was the simplest and quickest solution I found:
http://sondreb.com/blog/post/hyper-v-making-template-virtual-machines.aspx