SimilarWeb - SimilarWeb.com is a website analysis tool that gives you analytics information for any website.

Google Groups - Google Groups allows you to create and participate in online forums and email-based groups with a rich experience for community conversations.

Site Rank Data - View historical rank information of websites via time series charts.

DownToMeet - DownToMeet is a platform to organize, find, and attend group events.

Quantcast - Quantcast Corporation is a digital marketing company that provides free audience demographics measurement and delivers real-time advertising.

Mighty Networks - Mighty Networks enables entrepreneurs, organizations, and companies to create and grow a community-powered brand.