Bloafer

Use this plugin to apply <a href="https://wordpress.org/extend/plugins/share-rail/screenshots/" rel="ugc">floating shares</a> to your posts and pages.
This is very similar to the one found on mashable.com.

Share Rail

Use this plugin to apply floating shares to your posts and pages.

hebeisenconsulting

Social site sharer links widget takes your site url and blog name to construct social share links in any widget placement. Simply “Click and Forget.” No complicated configuration needed at all, however you can choose which ones to hide in the widget settings panel.

Social Site Sharer Links Widget

Social site sharer links widget automatically places popular social share links in a widget placement…

Share Rail vs Social Site Sharer Links Widget