Notezilla is a sticky notes app for Windows.

lumio is an online content organizing platform.

utWiker is designed to store notes in a tree. Such programs are called "outliner", personal wiki, or tree-like editors.

SuperNotecard helps writers of fiction and nonfiction with its tools.

Nimbus Note is a powerful notes app and organizer.

nvpy is a simplenote-syncing note-taking tool inspired by Notational Velocity (and a little bit by nvALT too) on OSX and ResophNotes on Windows.

Elephant is a notetaker with a classic interface.