Top Similar Sites - Top Similar Sites helps you find similar, alternative or related sites to any website instantly.
PitchWall - Browse new startups, and submit your mobile app/games startup's beta page here.
FreeSitesLike - FreeSitesLike is a user contributed website dedicated to offering its visitors with plenty of options to a specific website.
Product Hunt - A website that lets users share and discover new products
SimilarSites - Easily find more sites like those you like.
SimilarPages.com - SimilarPages has found and classified millions of interesting sites hidden due to low popularity with the goal of helping you discover and search a larger portion of the web