In putting the Avalon Task Manager sample back together, I found myself constantly wanting to tweak the transforms on the mesh and the camera values, like position and what not, and I kept having to recompile to see my adjustments. With this in mind, I went back to an earlier sample I started on modeling primitives and ported it to the Beta 1 RC, adding some new features. I am now calling this tool Sandbox3D, which you can download the source. This tool allows you to manipulate your mesh, see the values and use those values when placing your viewport in an application.
The sliders use Avalon databinding to wire up the coordinates. In a couple cases, I was able to do the binding directly in XAML; in other cases, I created a wrapper object in code. I based much of the databinding off of the connecteddata\colors sample in the SDK called "Showing System Colors Using Data Services", which I would highly recommend.
Features I'd like to add:
If you feel like hacking at this sample, please do -- and let me know how you change it. If we get enough momentum, maybe we can make it a GotDotNet workspace or SourceForge project...