Based on the idea behind Notational Velocity, it is designed to focus on organizing plain text notes that are saved automatically. Just write your note and don't worry about saving them. Open Notes again and you'll see all your notes

Penzu is a free online diary and personal journal that combines privacy and ease of use to make writingonline as simple and intuitive as writing on a pad of paper.

Exports your Simplenote notes to plain text, CSV, JSON, XML, YAML, and Evernote archive formats. Two easy steps. Completely free.