You can use Google SketchUp to create, modify and share 3D models.
Google SketchUp is software that you can use to create 3D models of anything you like.
Most people get rolling with SketchUp in just a few minutes.

Redecorate your living room. Design a new piece of furniture. Model your city for Google Earth. Create a skatepark for your hometown, then export an animation and share it on YouTube. There's no limit to what you can create with SketchUp.
You can build models from scratch, or you can download what you need. People all over the world share what they've made on the Google 3D Warehouse. It's a huge, searchable repository of models, and it's free.
What's New in Google SketchUp 7
Fast and reliable
We've made SketchUp even more intuitive, added tools for power users, and made it easier to find and share models with the world.
We've made SketchUp easier to use.
With edges that automatically break other edges where they cross, objects that are smart enough to know how they should behave when you interact with them, and drawing hints that are clearer and more consistent, Google SketchUp 7 is the most intuitive SketchUp ever.
It's all about collaboration and sharing.
In SketchUp 7, you can search for models in the Google 3D Warehouse right from the Component browser, take credit for what you contribute, keep track of your collaborators, and generally bask in the glow of knowing you're part of the worldwide 3D community.

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