Today there was a topic on HN about Vim.js, a JavaScript port of Vim. Some people were asking about a way to integrate the Vim editor with Github. Github currently uses Ace editor, and I remembered that it had a Vim mode from the time when I was implementing Ace with Datazenit. You can press CTRL+, or CMD+, (depends on your OS) to access Ace’s settings menu and enable Vim mode there (screenshot).