Pocket - When you find something you want to view later, put it in Pocket.
Qikipedia - Instant Wikipedia summary cards on any web page
Raindrop.io - All your articles, photos, video & content from web & apps in one place.
Newsit - Find the discussion around the page you're looking at!
Tettra - Tettra is a company wiki that helps teams manage and share organizational knowledge.
Anycomplete - The magic of Google Autocomplete while you're typing