you can try by firing the trigger event on the element that the tip is attached to.
for example - if you have
<a href="#" id="gethelp" class="tip" rel="Click here to sign in through facebook">what's this?</a>
<script type="text/javascript">
// domready etc.
var myTips = new Tips('a.tip');
// force the gethelp one up:
$("gethelp").fireEvent("mouseenter");
</script>
http://github.com/mootools/mootools-more/blob/master/Source/Interface/Tips.js
you may be able to do myTips.show(element); also although the whole concept is flawed:
mootools tooltips are basically following your mouse around as you mouseover an element. as such, they are event driven and the tooltips are pre-built in the vicinity of the target element. by showing one without the mouseenter event, it will look a bit odd...
Dimitar Christoff
2009-10-29 12:00:12