Web Apps

PHP-Proxy - a web-based proxy script designed to be fast, easy to customize, and be able to provide support for complex sites such as YouTube and Facebook

RSS-Bridge - the RSS feed for websites missing it

searX - a privacy-respecting, hackable metasearch engine

Trade-Free Planet - powered by moonmoon, a simple php app for showing several feeds on one page

TROM translations - powered by TiddlyWiki, a non-linear personal web notebook

References

Awesome Web Apps (that work without login) - Curated list of awesome web apps that work without requesting you to create an account.

Free Web Apps - Easy to use, safe, free apps that run in the browser.

Electron Apps - Desktop GUI applications using web technologies: combines the Chromium rendering engine and the Node.js runtime.