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.
SimilarSites - Easily find more sites like those you like.
Top Similar Sites - Top Similar Sites helps you find similar, alternative or related sites to any website instantly.
Growing Page - Browse web projects and evaluate them by multiple criteria.
PitchWall - Browse new startups, and submit your mobile app/games startup's beta page here.
Sites Like - Siteslike opened it's doors to the public on the 4th of december in 2008, since that time...