<?php
$regexp='/[a-zA-Z0-9\\.\\-\\+]+@[a-zA-Z0-9\\.\\-\\+]+[\\.]([a-zA-Z0-9\\.\\-\\+]+[\\.])?[a-zA-Z0-9\\.\\-\\+]+/';
$text="you+me@some.domain-domain.com";
$matches=array();
preg_match_all($regexp, $text, $matches);

var_dump($matches);