Google+ platform websites integration using the Google+ platform tag.
Shareaholic is an all-in-one content amplification and monetization platform, that includes related content recommendations, promoted content, social sharing and more
The Tweet Button is a small widget which allows visitors to share content and connect on Twitter.
Sites who has this tag are verfied by google to use WebMaster tools
By adding rel="home" to a hyperlink, a page indicates that the destination of that hyperlink is the homepage of the site in which the current page appears.