3DBrowser for 3D Users with Polygon Cruncher
by Mootools
A third party software for Sketchup (windows explorer thumbnailer, mesh optimizer...)
GroupBy
by Smustard Team
Explodes model and groups all entities by layer or material
PolyTrans 3D File Conversion System for SketchUp
by Okino Computer Graphics, Inc.
Cross Convert all Major 3D CAD, DCC & VisSim 3D File Formats for SketchUp