Content Syndication - js help pls

[YabbaDabba]

I've got the basics working.

However, for variety's sake I would like to display the latest 5 threads from a randomly selected forum. I have a random num generator and can select and assign forum #'s accordingly, but with the "forumids=X" hardwired into the script tag, I'm at a loss on how to randomize it. I think I want to replace "X" with a js variable. Is this feasible, and if so, how? Or do I need a completely different approach? I've hit my js limit.

Any help would be greatly appreciated.

[YabbaDabba]

This block generates the random num, ranks results, and creates variables:

<!-- // Hide from non-Java browsers
// Insert a list of recent activity
// for a random (sub)-forum

today = new Date();
RandomSeed = today.getTime() % 214783647;
RandomSeed = ((214013*RandomSeed)+2531011) % 214783647;
var y = Math.round((RandomSeed/214783647)*100);

if (y >= 76)
	{var HotForum="forum 1 title"; ForumNum="1";}

else if (y >= 51 && y <=75 )
	{var HotForum="forum 2 title"; ForumNum="2";}

else if (y >= 26 && y <=50 )2
	{var HotForum="forum 3 title"; ForumNum="3";}

else if (y <= 25)
	{var HotForum="forum 4 title"; ForumNum="4";}

else
	{var HotForum="forum 1 title"; ForumNum="1";}

var HotTopics="LATEST: "+HotForum+"";
document.write(HotTopics);

//--></SCRIPT>

This block invokes the content syndication routine:

<script type='text/javascript' src='http://www.examplesite.com/forums/external.php?type=js&forumids=1'></script>

(The above tag is written to call results from forum 1 only. I woulld like it to use +ForumNum+ as defined in the first block so that I can match up forum result with the forum title.)

And the following block writes out the first 5 threads for the selected forum (as part of a table):

<script type="text/javascript">
<!--
for (i = 0; i < 5; i++)
{
document.writeln("<tr ><TD><a href=\"http://www.examplesite.com/showthread.php?threadid="+threads[i].threadid+"\">"+threads[i].title+"</a></TD></tr>");
}
//--></SCRIPT>

Any ideas? Thanks in advance.
<newbie>