Evernote

Evernote is a program that lets you capture all of your thoughts, ideas, and inspirations, into a single place. Access everything whenever you need it from your PC, even when offline. You create notes containing text, webclips, snapshots, to-dos, PDFs, and more. In addition, Evernote works across the computers and phones you use daily, allowing you to capture something in one place and then access it from another.

The official website of Evernote is at http://www.evernote.com.