Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Wondershare PDFelement - All-in-one PDF editor
FreeCAD - An open-source parametric 3D modeler
Foxit PhantomPDF - Edit PDF files with our feature-rich PDF Editor. Download Foxit PDF Editor to convert, sign, scan / OCR & more. A speedy PDF Editor alternative to Adobe Acrobat.
meshmixer - meshmixer is an experimental 3D modeling tool for making 3D mashups without too much hassle.
Google Docs - Create a new document and edit with others at the same time -- from your computer, phone or tablet. Get stuff done with or without an internet connection. Use Docs to edit Word files. Free from Google.