Similar Tech - SimilarTech offers a Sales Insights platform which helps companies uncover their ideal market by crawling the sourcecode of over 300M sites.
Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
DataBasic - Easy-to-use web tools for beginners
BuiltWith - Find out the technology behind websites
MetaSurvey - MetaSurvey provides light and high engagement surveys for e-commerce.
What CMS - WhatCMS.org looks at a variety of factors within a webpage to determine what CMS a website is using.