Communifire - Enterprise Social Collaboration Software
PenPal World - Connect with people all over the world
LS Intranet - LS Intranet is a corporate intranet that facilitates multiple employees collaborating on projects, and working in synergy.
Nido - Slack for college students
Unily - Unily is a cloud-based intranet solution designed by SharePoint consultancy BrightStarr.
Frysbe - Frysbe: Make global friends at random and the fling app comes up with features to send messages to strangers from every corner of the world to expand your social circle.