Evernote (Windows/Mac, Free)

Pencil and Paper,

Microsoft OneNote (Windows, Shareware),

Microsoft OneNote is a killer note-taking app that integrates with every corner of your Windows PC.

Google Notebook (Web-based, Free)

Google Notebook is a web-based note-taking application that brings Google’s familiar interface and excellent search capabilities to your notes.

Personal Wiki

Get more information @ Life hacker

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