Albacross - The world's first free B2B Lead Generation Network. Albacross help companies master their B2B digital marketing with Lead Generation and targeted marketing
BuiltWith - Find out the technology behind websites
Apollo.io - Apollo’s predictive prospecting, sales engagement, and actionable analytics help the teams to reach its full revenue potential.
Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
What CMS - WhatCMS.org looks at a variety of factors within a webpage to determine what CMS a website is using.
Similar Tech - SimilarTech offers a Sales Insights platform which helps companies uncover their ideal market by crawling the sourcecode of over 300M sites.