Get results from ArcMap's built-in measure tool.

Does anyone have a clue how to programmatically access the results of ArcMap's built-in measure tool (the little ruler) via ArcObjects?

I have a custom button on a form to launch the tool. Ideally, upon double-clicking at the end of a measurement operation I would grab the result behind the scenes and populate a field in a specified feature class. I just need to know how to get the result. I'm developing an add-in using C# .NET.

Thanks,
Evan.