php parallel
http://www.phpied.com/simultaneuos-http-requests-in-php-with-curl/
http://stackoverflow.com/questions/6107339/parallel-processing-in-php-how-do-you-do-it
http://stackoverflow.com/questions/45953/php-execute-a-background-process
http://phplens.com/phpeverywhere/?q=node/view/254