Alex Schreyer has done a very nice job of putting these plugins together. We will be doing a list of some of our favourites, but in the meantime here they are:
Most popular SketchUp plugins – 2010 Update – by [as]
A lighthearted blog about SketchUp and the non-profit "DesignerDojo" Initiative whose mission is to teach kids SketchUp and 3D modeling for free. Sponsored by Viewsion- Ireland's Trimble SketchUp Authorised Training Centre.