Extending The Windows Vista Grace Period to 120 Days
 

Found this interesting...

Every Vista DVD includes the ability to install any edition of Vista without a product key. When you install without a product key, you get an automatic 30 day evaluation period.* This probably isn't news to anyone.

What may be news to you, however, is that you can easily extend the 30-day Windows Vista grace period to 120 days. No hacks required. This is an official, supported operation directly from Microsoft.

To extend the grace period another 30 days, simply start a command prompt as Administrator, and issue this command:

slmgr -rearm

Reboot for the change to take effect, and voila, you have 30 more days. You can only extend three times, so the total grace period for a Vista evaluation is 120 days.

Source: Bink.nu

nice find, MCore!