Mac OS X only: Donationware application Sidenote adds an unobtrusive sidebar to your Mac desktop for taking and organising multiple rich text notes. Under normal circumstances, Sidenote takes up a couple of pixels on the edge of your screen (though you can make it completely invisible in the Preferences), so it doesn't take any space until you need it. You can invoke Sidenote by either hovering your mouse over that edge or with the user-definable keyboard shortcut. In fact, virtually every aspect of the program is accessible via a keyboard shortcut, which any keyboard lover can appreciate. The application manages multiple notes, prints, emails, and exports notes, and is almost entirely customisable. Sidenote is donationware, Mac OS X only.