this is the one way routine Command and Conquer: Tiberian Sun uses to encrypt user passwords. pretty weak algorithm and extremely old game but, thought it would be fun to share. needed this to have the ability to match credentials for a server i'm developing. :)

<?php
echo apgar('password'); //result WaIMMsbf

function apgar( $a ) {
  if ( strlen( $a ) == 8 ) {
    $u = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
    for ( $i = 0; $i <= 7; $i++ ) {
      $r = ( ( $i == 0 ) ? 0 : ord( $a[8 - $i] ) );
      $x = ( ord($a[$i]) & 1 ) ? ( ord($a[$i]) << 1 ) & $r : ord($a[$i]) ^ $r;
      $o[] = substr($u, ($x & 0x3f), 1);
    }
    return implode('', $o);
  }
}
?>