HexView Beta 9.9.2006:

We have decided to make a preview (beta) version of HexView available to the public.

HexView is a .NET component that allows software developers to easily add a hex viewer to any Windows Forms application. 

This version is still under development but is useful enough to just display hex data.  It is the same component that powers the XL Delete preview file feature.  Learn more about HexView here.