Unlimited Values Weight
In a multi-value text field, and assuming D7, the values are something like this:

// if set, this is the first value...
$node-&gt;FIELD_NAME[$node-&gt;language][0]['value']
// if at least one set, this is the last value...
$node-&gt;FIELD_NAME[$node-&gt;language][count($node-&gt;FIELD_NAME[$node-&gt;language])-1]['value']


so depending on what you mean by 'on top,' one of these values is most probably what you are looking for.  (If D6, just take out the [$node-&gt;language] part)