CrunchBase is the free database of technology companies, people, and investors that anyone can edit.

LinkedIn strengthens and extends your existing network of trusted contacts. LinkedIn is a networking tool that helps you discover inside connections t...

Twitter is without a doubt the best way to share and discover what is happening right now.

Facebook is a social utility that connects people with friends and others who work, study and live around them. People use Facebook to keep up with fr...

AngelList is a platform for startups

Find online Yellow Pages business listings, phone numbers, addresses, maps, driving directions and more in the YELLOWPAGES.COM online directory.

foursquare

YouTube is a place to discover, watch, upload and share videos.

Yahoo! Local has business reviews, top rated services, and events near you. Use interactive maps, driving directions reviews and ratings to find the r...

San Francisco - User Reviews and Recommendations of Top Restaurants, Shopping, Nightlife, Entertainment, Services and More at Yelp

Yellow Pages with ratings and reviews

Quora is a continually improving collection of questions and answers created, edited, and organized by everyone who uses it.

Yellow Pages by Superpages.com - Find local businesses with our online Yellow Pages: Local Search, Ratings and Reviews, Maps, Driving Directions, Traf...

The global platform for startup funding and angel investment . For entrepreneurs and investors, the people, the insights, and the tools for successful...