The plugin has a website also
wxSU is a plugin for Google SketchUp 6 that extends the SketchUp API with the capabilities of wxRuby. wxSU bundles wxRuby to provide a cross-platform, pure Ruby solution for implementing GUI dialogs in your SketchUp plugins.
The plugin provides several tools to ease the process of preparing a model for 3D printing:
-Resurfacer: Shrinkwrap a model into one continuous, solid mesh
-3D Print Visualization Style: A visual style that highlights problem areas in a model
-Layerize tool: Easily move all geometry within components and groups to a layer
-Smooth/Unsmooth: Toggle smoothing on a model's rounded geometry