I needed a way to trim all white space and then a few chosen strings from the end of a string.  So I wrote this class to reuse when stuff needs to be trimmed.  
<?php
class cleaner {
function cleaner ($cuts,$pinfo) {
$ucut = "0";
$lcut = "0";
while ($cuts[$ucut]) {
$lcut++;
$ucut++;
}
$lcut = $lcut - 1;
$ucut = "0";
$rcut = "0";
$wiy = "start";
while ($wiy) {
if ($so) {
$ucut = "0";
$rcut = "0";
unset($so);
}
if (!$cuts[$ucut]) {
$so = "restart";
} else {
$pinfo = rtrim($pinfo);
$bpinfol = strlen($pinfo);
$tcut = $cuts[$ucut];
$pinfo = rtrim($pinfo,"$tcut");
$pinfol = strlen($pinfo);
    if ($bpinfol == $pinfol) {
    $rcut++;
    if ($rcut == $lcut) {
    unset($wiy);
    }
    $ucut++;
    } else {
    $so = "restart";
    }
}
}
$this->cleaner = $pinfo;
}
}
$pinfo = "Well... I'm really bored...<br /><br>     \n\t <br><br /><br>     \r\r <br>\r<br /><br>\r      \n<br>      <br />\t";
$cuts = array('\n','\r','\t',' ',' ',' ','<br />','<br>','<br/>');
$pinfo = new cleaner($cuts,$pinfo);
$pinfo = $pinfo->cleaner;
print $pinfo;
?>
That class will take any string that you put in the $cust array and remove it from the end of the $pinfo string.  It's useful for cleaning up comments, articles, or mail that users post to your site, making it so there's no extra blank space or blank lines.