node.js vs. PHP + libevent (or libev)

http://webdevrefinery.com/forums/topic/5309-libevent-for-php/page__p__45362#entry45362 :: Libevent for PHP! - webdevRefinery Forum http://blog.zorinaq.com/?e=34 :: node.js Internals and Powerful Non-blocking I/O Libraries - Zorinaq

http://stackoverflow.com/questions/5333619/how-is-nodejs-different-from-running-libevent :: c++ - How is nodejs different from running libevent? - Stack Overflow http://news.ycombinator.com/item?id=1510537 :: What is so great about node.js? libevent has been around for ages, and it’s got … | Hacker News

Normal way of non-blocking socket communication: Creating a PHP socket server « FUNCTION Can PHP asynchronously use sockets? - Stack Overflow

React (node in php)

http://nodephp.org/ :: React
http://gonzalo123.wordpress.com/2012/05/21/database-connection-pooling-with-php-and-react-node-php/ :: Database connection pooling with PHP and React (node.php) « Gonzalo Ayuso | Web Architect

We now have an experimental libev-based EventLoop implementation. This should be even faster than the libevent one.
https://twitter.com/reactphp/status/224108214147485697 :: Twitter / reactphp: We now have an experimenta ...

Others based on libevent

phpDaemon
    Asynchronous server-side framework implemented in PHP using famous libevent
    http://phpdaemon.net/ :: phpDaemon
    http://phpdaemon.net/examples.html :: Examples | phpDaemon

https://github.com/fhoenig/Kellner :: fhoenig/Kellner
https://github.com/theUniC/Hawk :: theUniC/Hawk

Advances in PHP

http://technosophos.com/content/php-getting-better :: Is PHP Getting Better? | TechnoSophos
http://getcomposer.org/ :: Composer

http://gonzalo123.wordpress.com/2010/07/27/clustering-php-applications-tips-and-hints/ :: Clustering PHP applications. Tips and hints « Gonzalo Ayuso | Web Architect
http://gonzalo123.wordpress.com/2011/07/25/using-node-js-to-store-php-sessions/ :: Using node.js to store PHP sessions « Gonzalo Ayuso | Web Architect

Connection Pool in React:
http://gonzalo123.wordpress.com/2012/05/21/database-connection-pooling-with-php-and-react-node-php/ :: Database connection pooling with PHP and React (node.php) « Gonzalo Ayuso | Web Architect
https://github.com/junamai2000/mod_namy_pool :: junamai2000/mod_namy_pool

PHP Framework written as extension in C (not mature)
http://stackoverflow.com/questions/1347500/is-there-any-php-framework-written-as-a-c-extension :: Is there any PHP Framework written as a C extension? - Stack Overflow
http://phalconphp.com/ :: Phalcon PHP | High performance PHP framework
http://pecl.php.net/package/yaf :: PECL :: Package :: yaf