Async (EventMachine) HTTP client, with support for:
o   Asynchronous HTTP API for single & parallel request execution
o   Keep-Alive and HTTP pipelining support
o   Auto-follow 3xx redirects with max depth
o   Automatic gzip & deflate decoding
o   Streaming response processing
o   Streaming file uploads
o   HTTP proxy and SOCKS5 support
o   Basic Auth & OAuth
o   Connection-level & Global middleware support
o   HTTP parser via http_parser.rb
o   Works wherever EventMachine runs: Rubinius, JRuby, MRI

WWW: https://github.com/igrigorik/em-http-request