Enter a URL, set some headers, view the response, then share it with others. Perfect for demoing and debugging APIs.
(Full Story: http://www.hurl.it/ )
$ curl -I google.com
(Full Story: Display HTTP-header using curl | commandlinefu.com)
Typhoeus is a fearsome Ruby library that enables parallel HTTP requests while cleanly encapsulating handling logic. Specifically, it uses libcurl and libcurl-multi to run HTTP really fast. Further, it’s designed with the focus of creating client libraries that work with web services. These could be external services like Twitter or systems like CouchDB and SimpleDB or custom web services that you write yourself.
(Link: Breath fire over HTTP in Ruby with Typhoeus)