Mac OS X
From Misc Data Digs
The OS includes a kernel cheekily named com.apple.Dont_Steal_Mac_OS_X for any Intel-capable versions of the OS. This extension prevents users from loading the OS onto non-Apple hardware. It loads this message into RAM:
Your karma check for today: There once was a user that whined his existing OS was so blind, he’d do better to pirate an OS that ran great but found his hardware declined. Please don’t steal Mac OS! Really, that’s way uncool. (C) Apple Computer, Inc.