Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
MakCorps - Hotel Price Comparison API
BuiltWith - Find out the technology behind websites
HotelTonight Escape - The best getaway deals for tonight (or the weekend)
What CMS - WhatCMS.org looks at a variety of factors within a webpage to determine what CMS a website is using.
Hotellook - Compare hotel deals from all the leading booking agencies