Site Rank Data - View historical rank information of websites via time series charts.
cutestat - Website Stats and Valuation. CuteStat.
Q-Stats - Get free marketing insights for every question on Quora.
WebsiteOutlook - WebsiteOutlook is an all-in-one website that provides you detailed information on famous websites based on various data sources like traffic, page rank, and estimated ad revenue.
Seoxan - check seo report for any website, alexa ranking, server information, meta tags, authority, page speed and more
Rankchart - Rankchart is one of the unique websites that allows you to examine your websites or watch competitors and locate rich information about website technologies, site reputation, errors, SEO, and ad-word recommendations.