Posts in three columns

I want to have three columns instead of two.

What do I change?

<table cellpadding="10" cellspacing="10" border="0">
    <?php $column = 1; ?>
    <?php // The LOOP. Do this for all posts:
    while (have_posts()) : the_post(); $postcount++; ?> 

        <?php if ($column == 1) echo "<tr>"; ?>

        <td class="column<?php echo $col;?>" style="vertical-align: top">

			<div class="post" id="post-<?php the_ID(); ?>">

				<h1><a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title(); ?>"><?php the_title(); ?></a></h1>

				<div class="descr"><?php the_time('l, F jS Y, G:i a T') ?></div>

	<div class="entry">

                      <?php the_content('Read the rest of this entry &raquo;'); ?>

				</div>

			</div>

        </td>

        <?php if ($column == 2) echo "</tr>"; (($column==1) ? $column=2 : $column=1); ?>

    <?php // END of the LOOP
    endwhile; ?>
</table>

Also I want the post to go down than to the side.

e.g.

1 2
3 4
5 6

I want:

1 4
2 5
3 6