Web Apps

Proxy

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 Feeds

Moonmoon - a simple php app for showing several feeds on one page

RSS-Bridge - the RSS feed for websites missing it

Search

searX - a privacy-respecting, hackable metasearch engine

Torrent

βTorrent - fully-featured WebTorrent client

Wiki

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.