Softorino YouTube Converter - Download YouTube video & audio. Watch and listen offline
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
Yout - YouTube to Mp3 Converter
httpbin(1) - HTTP request and response service
You-Get - Command-line utility to download media contents from the web
Endpoints - View and respond to requests on an HTTP endpoint