Rewrite multiple CSS links (and HEAD styles) to a single sheet.

.htaccess

# Uncomment (remove the hash from) ONLY ONE of the following lines (first one is already uncommented):
AddHandler application/x-httpd-php .html .htm
# AddHandler application/x-httpd-php5 .html .htm
# AddType application/x-httpd-php .html .htm
# AddHandler x-httpd-php .html .htm
# end of the one-line options (use the first one that doesn't cause an error on your server).

# Or, if you are stranded on GoDaddy, uncomment BOTH following lines:
# AddType application/x-httpd-php .htm .html
# AddHandler x-httpd-php  .htm .html

# change the following path to reflect YOUR server, not mine
php_value auto_prepend_file /data/www/scripty/masher/masher.php

masher.php

<?php
ob_start();
$code = file_get_contents($_SERVER['SCRIPT_FILENAME']);
$now = filemtime($_SERVER['SCRIPT_FILENAME']);
ob_end_clean();
$out = array();
$sheets = array();
$inline = array();
$style = '';
$prefix = '';
$ending = '>';
$base = str_replace($_SERVER['DOCUMENT_ROOT'], '', $_SERVER['SCRIPT_FILENAME']);
$base = preg_split('/[\/\.]/', $base, -1, PREG_SPLIT_NO_EMPTY);
array_pop($base);
$base = implode('_', $base);
$lines = preg_split('/[\n\r]+/', $code, -1, PREG_SPLIT_NO_EMPTY);
$styling = false;
foreach($lines as $line){
  if($styling && preg_match('/<\/style>/i', $line)){
    $styling = false;
  }elseif(!$styling && preg_match('/<style/i', $line)){
    $styling = true;
  }elseif($styling && preg_match('/<!--|-->/', $line)){
    //ignore the comment
  }elseif($styling){
    $inline[] = trim($line);
  }elseif(preg_match('/<\/head>/i', $line)){
    $out[] = preg_replace('/<\/head>/i', '', $line);
    $out[] = '  <link rel="stylesheet" href="' . $prefix . '/' . $base . '.css"' . $ending;
    $out[] = '</head>';
  }elseif(preg_match('/<link .*?rel="stylesheet/i', $line)){
    if(preg_match('/\/>/', $line)) $ending = '/>';
    $sheet = preg_replace('/.+?href="(.+?)"[^>]*>/i','$1', $line);
    if(!preg_match('/https?:\/\//i',$sheet)){
      $sheets[] = $sheet;
      $prefix = dirname($sheet);
    }else{
      $out[] = $line;
    }
  }else{
    $out[] = $line;
  }
}
$offset = '';
foreach($sheets as $sheet){
  if(empty($offset)) $offset = dirname($_SERVER['SCRIPT_FILENAME']) . '/' . dirname($sheet);
  $link = dirname($_SERVER['SCRIPT_FILENAME']) . '/' . $sheet;
  if(file_exists($link)){
    $style .= file_get_contents($link) . "\n";
  }else{
    $link = "\t<link rel=\"stylesheet\" href=\"$link\" type=\"text/css\"$ending\n</head>";
    $code = preg_replace('/<\/head>/', $link);
  }
}
$style .= implode("\n", $inline);
file_put_contents($offset . '/' . $base . '.css', $style);
print implode("\n", $out);
exit;
?>