Microsoft has released a Free Evaluation version of Windows 8. The evaluation copy of Windows 8 Enterprise is valid only for 90 days after activation, and once expired, cannot be upgraded. It is intended for developers, but presents a safe method for those who don't have Technet/MSDN access and want to try the final version of Windows 8 right now.
Download:
Download Windows 8 Enterprise Evaluation
Download:
Download Windows 8 Enterprise Evaluation