Windows Vista - http://www.vistaarticles.com
Install Windows Vista without Product Key
http://www.vistaarticles.com/articles/79/1/Install-Windows-Vista-without-Product-Key
By 
Published on 10/21/2006
 
For 14 Days.

Install Windows Vista without Product Key

Click "Next" on the key screen during install.

You can use it for 14 days without key or activating.