Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Synology Note Station - Without needing to spend money on Evernote, Synology Note Station provides a desktop client to organize all your random notes in one place.
TaskPaper - Plain text to-do lists for Mac
UpNote - A beautiful and clean cross-platform app for notes organizer
Listy Beta - The things you love, privately saved and beautifully listed
Notesnook - Notesnook is a simple and private note taking app that keeps your notes organized and synced on your phone, tablet and computer.