Top Alternatives to Penzu

Evernote is a note taking application which keeps the notes taken in sync across all platforms using its cloud infrastructure.

Notezilla is a sticky notes app for Windows.

Joplin is an open-source free note taking and to-do application.

CherryTree is an hierarchical note taking application, featuring rich text and syntax highlighting, storing data in a single xml or sqlite file.

NixNote is an open source client for Evernote.

RedNotebook is an open source diary and journal software for Linux, Windows and Mac.

ResophNotes is a fast note writing tool and a Simplenote client on Windows.

Day One is a simple journal application for the Mac, iPhone, and iPad.

nvALT 2 is a fork of the original Notational Velocity with some additional features and interface modifications, including MultiMarkdown functionality.

Leanote is a self-hosted note taking app.

Guide is an application that allows you create documents ("guides") which inherently have a tree (which you can modify as you please) and text associated with each node of the tree.

Journey is a journal app companion that keeps your private memories for a lifetime.

BeeCanvas is an online whiteboard based visual collaboration tool.

Elephant is a notetaker with a classic interface.