Alternate code in my index.php

I’m looking to alternate or swap a line of code in my index.php file everytime the page gets re-loaded. I’m new to wordpress and php coding so please go gentle.

Here is a small chunk of code from my index.php:

<div id=”content” class=”narrowcolumn”>

<div style=”height:85px”><?php flshow(63); ?></div>

<?php if (have_posts()) : ?>

This code shows a flash carousel on my site that has around 7 images in it:
<div style=”height:85px”><?php flshow(63); ?></div>

I also have around 7 more of these flash carousels. The code for each one goes like this:

<div style=”height:85px”><?php flshow(64); ?></div>
<div style=”height:85px”><?php flshow(65); ?></div>
<div style=”height:85px”><?php flshow(66); ?></div>
<div style=”height:85px”><?php flshow(67); ?></div>
etc..

I was wondering if there is a way to have wordpress show a random flash carousel each time someone visits my site.

For example it would show this carousel:
<div style=”height:85px”><?php flshow(63); ?></div>
and then when the page gets reloaded it would show this carousel: <div style=”height:85px”><?php flshow(64); ?></div>

Thanks for any help.