Replace any ‘http://’ text URLs with clickable hyperlink that open in a new window:
<?php function textToHyperlinks( $string ) { return preg_replace( '@(https?://([-\w\.]+[-\w])+(:\d+)?(/([\w/_\.#-]*(\?\S+)?[^\.\s])?)?)@', '<a href="$1" target="_blank">$1</a>', $string ); }