Català - Castellano - Deutsch
I recently posted on some Plugins by TIG:
These are part of a more complete set of Plugins by TIG that contains very other useful tools. The ones detailed here are the ones I found more useful (because I needed to use them), but the others are quite handy too. Installing the full set of tools from here, will add a Toolbar to SketchUp that will allow you to easy access all the Plugins on this set.
Alternatively, you can access them going to Plugins --> Extrusion Tools.
The Plugin Set can be downloaded here.
If you are new to SketchUp chek here to know how to Install SketchUp Plugins.