This is an awesome html aware excerpt.

index.php

<?php

/**
 * @return string
 */
function html_excerpt($string,$length=150,$ending="&hellip;") {
    $opening_regex = '/((?:<[a-zA-Z0-9="\':.,;\-() ]*>)*)(.*)/';
    $closing_regex = '/(<\/[a-zA-Z0-9="\':.,;\-() ]*>)/';
    $string = trim($string);
    $str_len = 0;
    $new_string = '';
    $c = 0;
    do {
        preg_match($opening_regex, $string, $matches);
        preg_match($closing_regex, $matches[2], $closing_tag_string);
        $split = preg_split($closing_regex, $matches[2], 2);
        $append = "";
        if ((strlen($split[0]) + $str_len) < $length)
        {
            $actual_string = $split[0];
        }
        else
        {
            $actual_string = substr($split[0], 0, $length - (strlen($split[0]) + $str_len));
        }
        $append = $matches[1].$actual_string.$closing_tag_string[0].$split[1];
        $new_string = $new_string.$append;
        $str_len += strlen($actual_string);

        $string = substr($string, strlen($append)-1);
        $string = trim($string);
        $c++;
    } while ($str_len < $length);
    return trim($new_string).$ending;
}