Preact.js - Preact is a fast 3kB alternative to React with the same modern API. Components & Virtual DOM.
SimilarWeb - SimilarWeb.com is a website analysis tool that gives you analytics information for any website.
Inferno - An extremely fast React-like javascript library for building modern user interfaces.
Website Informer - Website.informer: complete data lookup & free aggregated report on any domain including whois, visitors, IP & DNS details, competitors, owners, etc
Glimmer - Fast and light-weight UI components for the web
Site Rank Data - View historical rank information of websites via time series charts.