While at college, as we were studying for an IT course we ended up running a lot of virtual machines for Windows Server 2003, and Windows XP Pro clients.
One of the unforseen side effects of this however was that there was a 30 day countdown after install that couldn’t really be avoided. One by one, virtual machines would end up being un-bootable due to Windows Product Activation.
Being the spritely scallywag that I was, I knew of an activation patcher and made
winlogon.exe patches and registry scripts that would handily bypass this restoring the virtual machines to their former glory. These patches were installed on literally every machine by the end of the term.