You’d have to do something like this: {exp:weblog:categories «attributes go here»}<p>«everything that is already there»</p>{/exp:weblog:categories}
Arden, he’s using pMachine, not ExpressionEngine. 
It uses a function called weblog_categories.
<?php weblog_categories($id,"weblog","text"); ?>
Here’s some of the code:
// TEXT VERSION OF THE CATEGORY LIST
?>
<a href="<?php echo "$categorylink"; ?>"><?php echo "$category"; ?></a><br />
<?php
}
if (substr($id, 0, 1) =="C")
{
$link = "$pagespath$weblogpage";
if ($url_rewriting == 1) $link .= '/';
?>
<a href="<?php echo $link; ?>"><?php echo stripslashes($showallblurb); ?></a><br />
<?php
}
}
}
}
// END
It’s found in /pm/lib/category.fns.php. You could use another <br /> there, or put it inside <p></p> tags.
Seriously, you could use EECore instead, where you have many more options.
