Raindrop.io - All your articles, photos, video & content from web & apps in one place.
Pocket - When you find something you want to view later, put it in Pocket.
Diigo - Diigo is a powerful research tool and a knowledge-sharing community
wallabag - Save the web, freely.
Tagpacker - A free tool to quickly collect, organize, and share your favorite links.
Instapaper - Instapaper is a simple tool to save web pages for reading later.