Nullboard - Minimalist locally-stored kanban board / task list manager.
Refined GitHub - Browser extension that makes GitHub cleaner & more powerful
Waffle - Split screen picture conversations with friends
GitZip - Download or create a download link for a GitHub project folder/sub-folder or file.
Brisqi - Offline-first personal Kanban app
GitHub Hovercard - GitHub Hovercard provides neat hovercards for GitHub.