LDraw - LDraw is an open standard for LEGO CAD programs that allow the user to create virtual LEGO models...
Wondershare PDFelement - All-in-one PDF editor
LeoCAD - LeoCAD is a CAD program for creating virtual LEGO models.
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.
LDCad - LDCad is a multiplatform ...
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.