Wolfenstein 3D had these requirements:
* 286 Computer (386+ Strongly Recommended)
* 528k of conventional memory (2Mb total memory recommended)
* 3 meg of Hard Drive Space (for shareware)
* 8 meg of Hard Drive Space (for registered)
I could be terribly wrong, but I expect the Zune FreeScale process exceeds a 386 in performance, and we know it has more memory than 2 megs

So I think we should be able to do a little better than wolf3D actually.