Ask HN: Note-taking native application with search, backups etc

(I'm on OS X mostly)

I found a note taking application mentioned here some months ago that sounded very interesting. It had a good search, easy tagging, local storage and I think even some optional offsite storage/backup. (it was not a web-app).

Can anyone enlighten me which one it was? Or recommend any software with this property? At the moment I'm just using Sublime Text with multiple .txt files per project open and appending to that .txt file.