Sharingbuttons.io - Quickly generate social sharing buttons with a tiny performance footprint.
Shareaholic - Shareaholic is trusted by over 300000 brands, businesses, agencies, and individuals to grow website traffic and engagement 24 hours a day, 7 days a week.
Social Share Kit - Library of CSS/JavaScript social sharing tools
AddThis - AddThis free website tools include share buttons, targeting tools and content recommendations help you get more likes, shares and followers and keep them coming back.
SimpleShare.IO - A helper site to build buttons for sharing links on the various social sites, but without loading...
Dragula - A drag and drop library for developers