Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.
Wondershare PDFelement - All-in-one PDF editor
Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
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.
Strikethru - Strikethru is a kind of to-do list notebook for managing work lists and staying updated with the important tasks.
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.