64bit
The .NET Framework provides a fully managed, protected, and feature-rich application execution environment, simplified development and deployment, and seamless integration with a wide variety of programming languages. Note: This feature is not available in 64-bit versions of the Windows Server 2003 family. [Windows 2003 Feature Highlights]
Well ain't that a pisser. With all the talk about the Opteron out there, AMD got me giddy at the thought of 64bit fun, dual proc workstation fun. But alas, my hopes and dreams have been dashed yet again.