Speed Notes is a note-taking application for Dropbox and iPhone that offers a very simple interface inspired by the open-source Notational Velocity. Searching for and creating notes can be done entirely by typing in the text box on home screen…
Notes are stored as plain text files in your Dropbox.
Deft is an Emacs mode for quickly browsing, filtering, and editing directories of plain text notes, inspired by Notational Velocity. It was designed for increased productivity when writing and taking notes by making it fast and simple to find the right file at the right time and by automating many of the usual tasks such as creating new files and saving files.
org-velocity implements an interface for Org inspired by the minimalist notetaking program Notational Velocity. The idea is to allow you to amass and access brief notes on many subjects with minimal fuss.
I’m not an Emacs person so haven’t taken this for a spin, but judging by the documentation it looks like a bit of a must-have for Org-Mode fans.