Hacker News Front Page Explorer - A database of top ranking Hacker News front page posts
Readwise - Effortlessly rediscover and organize your Kindle highlights
Hacker News-cli - Browse Hacker News from your Terminal
Clippings.io - Organize the notes you make on your Kindle
Box Piper Hacker News - Re-Imagined Hacker News for this decade.
Klib - Kindle & iBooks Highlights Manager