Joplin - Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.
LINQPad - A scratchpad for C#, F# and VB code including Linq queries.
Boostnote - Boostnote is an open-source note-taking app.
Zeal - Zeal is an API Documentation Browser.
Day One - A simple journal application for the Mac, iPhone, and iPad. AboutTo learn more about Day One, see these two excellent reviews . PublishPublish is not available in Day One 2.
Devhelp - Devhelp is a GTK+/GNOME browser for API documentation; it works natively with gtk-doc (which is the...