AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
ClustrMaps widget is a visitor tracker, designed for general web and blog use.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
RevolverMaps is a collection of real-time visitor statistics widgets for website or blog. Interactive visitor mappings to a globe rendered by the Revolver Engine.
YouTube is a video sharing service where users can create their own profile, upload videos, watch, like and comment on other videos.