quick question about closest(), also...nextest() or similar?

quick question about closest(), also...nextest() or similar?


i've been using chains like this all over my webapp:
$(this).parents("li:eq(0)")
it seems that closest is a direct replacement for this and a
functional equiv of
$(this).closest("li").
also, is there anything like
nextest() that works outside the bounds of the parent container? for
example:
<span>
<b id="foo">bar</b>
</span>
<span>
<b>Hello!</b>
</span>
$("#foo").nextest("b") would return the second <b> node in the tree
following the current element, but not a sibling. right now i'm
needing to create funky ways to do this, unless i'm missing something.
right now i'm forced to do:
var $e = $("#foo");
var i = $("b").index($e);
var finally = $("b:eq(" + (i+1) + ")");
..also consider than in real life $e is not retrieved by id but is
"this" inside a function and often inside of a .each loop.
thanks in advance,
Leon