Despite Microsoft's next generation OS, Longhorn, is still years away from reaching 'final' state, pirates in Asia are selling a very early build of the OS for just slightly more than a dollar:

The Longhorn alpha is a pirated version of the edition distributed to programmers in October, and Reuters describes a Voleperson saying that installing the software on a PC as rather risky.
The Longhorn OS, which according to chief software architect Bill Gates recently, will cost as much as it cost for the US to put a man on the moon, is unlikely to appear before 2005.