[B00MER]

Little late but here is the code for this in 3.5.x:

{* divide subcategories into 2 columns www.cart-lab.com written for 3.5.x *}
{ include file="location.tpl" }
{if $active_modules.Bestsellers ne "" and $config.Modules.bestsellers_menu ne "Y"}



{include file="modules/Bestsellers/bestsellers.tpl"}
{/if}



{ include file="customer/main/navigation.tpl" }
{if ($navigation_page eq "")||($navigation_page eq "1")}{$current_category.description|regex_replace:"/[\n]/":"
"}

{/if}
{capture name=dialog}
{assign var="tmp" value="0"}
{section name=cat_num loop=$subcategories}
{if $subcategories[cat_num].category}{assign var="tmp" value="1"}{/if}
{/section}

{section name=cat_num loop=$subcategories start=1}

{math equation="x/2" x=$smarty.section.cat_num.max assign="counter" }

{if %cat_num.first%}
{if $tmp} [img]{if $current_category.icon_url}{$current_category.icon_url}{else}{$xcart_web_dir}/icon.php?categoryid={$cat}{/if}[/img] {/if}
<table border=0 width="100%" cellspacing=5><tr>
{/if}

<td width="50%"><font class="ItemsList">{ $subcategories[cat_num].category_name|escape }</font>
</td>

{if %cat_num.index% is div by 2}</tr><tr>{/if}
{*
<td align=right nowrap><font class=Text>
{if $config.Appearance.count_products eq "Y"}
{if $subcategories[cat_num].product_count}
{ $subcategories[cat_num].product_count } {$lng.lbl_products}
{elseif $subcategories[cat_num].subcategory_count}
{ $subcategories[cat_num].subcategory_count } {$lng.lbl_categories|lower}
{/if}
{/if}
</font></td>
</tr>
*}
{ if %cat_num.last% }
</tr></table>
{/if}
{/section}

{if $tmp and $products ne "" }
<br clear=_all><hr size=1 noshade>
{/if}
{include file="customer/main/products.tpl" products=$products}
{if $products eq "" and $tmp eq "0"}
{$lng.txt_no_products_in_cat}
{/if}
{/capture}
{include file="dialog.tpl" title=$current_category.category_name|regex_replace:"/.*\//":"" content=$smarty.capture.dialog extra="width=100%"}
{if $products eq ""}
{if $f_products ne ""}



{include file="customer/main/featured.tpl"}
{/if}
{/if}
{ include file="customer/main/navigation.tpl" }