Graphiq - Vivid, contextually-rich visualizations of the world's deepest knowledge graph.
SocialCompare - Platform of User-generated collaborative and interactive comparison tables.
vsChart.com - With vsChart.com you can compare products and a lot more.
AlternativeTo - AlternativeTo lets you find apps and software for Windows, Mac, Linux, iPhone, iPad, Android, Android Tablets, Web Apps, Online, Windows Tablets and more by recommending alternatives to apps you already know.
Versus - Find popular alternatives to anything in a jiffy
Slant.co - Slant is a collaboratively edited resource that helps you quickly make decisions.