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.
LinkAce - A selfhosted bookmark manager with advanced features.
Diigo - Diigo is a powerful research tool and a knowledge-sharing community
Bookmark Sidebar - Adds a toggleable sidebar with all your bookmarks at the edge of your browser window.
Bookmark OS - Bookmark OS is like Mac or Windows optimized for bookmarks.