Here's the relevant part of the page source code:
PHP Code:
<table class="tborder" cellpadding="6" cellspacing="1" border="0" width="100%" align="center">
<thead>
<tr>
<td class="tcat" width="100%"><strong> Available Subscriptions </strong></td>
</tr>
</thead>
<tr>
<td>Choose the type of membership you would like below. </td>
</tr>
<tr>
<td align="center" nowrap="nowrap"><br>
<table border="0" cellspacing="0" cellpadding="0" class="subscription">
<thead>
<tr>
<td>Membership Type:</td>
<td class="subscription_3">Free Member</td>
<td class="subscription_1">Premium Member</td>
<td class="subscription_2">Lifetime Member</td>
<td class="subscription_4">Vendor</td>
</tr>
</thead>
<tr>
<td>Recognition:</td>
<td class="subscription_3">None</td>
<td class="subscription_1"><img src="/forums/images/gixxer/misc/member_premium.gif" border="0" /></td>
<td class="subscription_2"><img src="/forums/images/gixxer/misc/member_lifetime.gif" border="0" /></td>
<td class="subscription_4"><img src="/forums/images/gixxer/misc/member_vendor.gif" border="0" /></td>
</tr>
<tr>
<td>
<span class="vbmenu_control" id="avatar" ><a href="/forums/register.php?nojs=1#goto_avatar" rel="nofollow">Avatar Size:</a> <script type="text/javascript"> vbmenu_register("avatar"); </script></span>
</td>
<td class="subscription_3">96 x 96px </td>
<td class="subscription_1">144x168px</td>
<td class="subscription_2">144x168px</td>
<td class="subscription_4">144x168px</td>
</tr>
<tr>
<td>Gallery Space:</td>
<td class="subscription_3">5 MB</td>
<td class="subscription_1">50 MB </td>
<td class="subscription_2">50 MB </td>
<td class="subscription_4">50 MB </td>
</tr>
<tr>
<td>Private Message Storage:</td>
<td class="subscription_3">50 Messages </td>
<td class="subscription_1">500 Messages </td>
<td class="subscription_2">500 Messages </td>
<td class="subscription_4">500 Messages </td>
</tr>
<!-- <tr>
<td>Less Ads:</td>
<td class="subscription_3">No</td>
<td class="subscription_1"> Vendor ads only</td>
<td class="subscription_2"> Vendor ads only</td>
<td class="subscription_4"> Vendor ads only</td>
</tr> -->
<tr>
<td>Colored Username:</td>
<td class="subscription_3">No</td>
<td class="subscription_1"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_2"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_4"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
</tr>
<!-- <tr>
<td>Images Allowed in Signature:</td>
<td class="subscription_3">No</td>
<td class="subscription_1"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_2"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_4"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
</tr> -->
<tr>
<td>Post in Classifieds:</td>
<td class="subscription_3">No</td>
<td class="subscription_1"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_2"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_4">No</td>
</tr>
<tr>
<td>Access to Club R Forum:</td>
<td class="subscription_3">No</td>
<td class="subscription_1"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_2"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_4"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
</tr>
<tr>
<td>Commercial Post:</td>
<td class="subscription_3">No</td>
<td class="subscription_1">No </td>
<td class="subscription_2">No </td>
<td class="subscription_4"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
</tr>
<!-- <tr>
<td>Forum T-Shirt:</td>
<td class="subscription_3">No</td>
<td class="subscription_1">No</td>
<td class="subscription_2"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
<td class="subscription_4"><img src="/forums/images/gixxer/misc/checkmark.gif">Yes </td>
</tr> -->
<tr>
<td>Price:</td>
<td class="subscription_3">Free</td>
<td class="subscription_1">1 Year <br>
US $15* </td>
<td class="subscription_2">Lifetime<br>
US $40 </td>
<td class="subscription_4">Monthly<br>
US $49* </td>
</tr>
<tr>
<td> </td>
<td class="subscription_3"><a href="http://www.gixxer.com/forums/register.php?mlvl=-1"><img src="/forums/images/gixxer/buttons/submit-free.gif" border="0" /></a></td>
<td class="subscription_1"><a href="http://www.gixxer.com/forums/register.php?mlvl=3"><img src="/forums/images/gixxer/buttons/submit-premiummember.gif" border="0" /></a></td>
<td class="subscription_2"><a href="http://www.gixxer.com/forums/register.php?mlvl=4"><img src="/forums/images/gixxer/buttons/submit-lifetimemember.gif" border="0" /></a></td>
<td class="subscription_4"><a href="http://www.gixxer.com/forums/register.php?mlvl=5"><img src="/forums/images/gixxer/buttons/submit-vendor.gif" border="0" /></a></td>
</tr>
</table>
<div class="fieldset" style="margin:0px; padding:3px">
Validity periods marked <strong class="highlight">*</strong> indicate that purchasing this subscription is recurring,<br> this means after the period is complete it will automatically be renewed.
</div>
<br></td>
</tr>
</table>
<!-- popup menu contents -->
<!-- forum tools menu -->
<div class="vbmenu_popup" id="avatar_menu" style="display:none">
<table cellpadding="4" cellspacing="1">
<tr>
<td class="thead">96 x 96 pixel Avatar
</td>
<td class="thead">144 x 168 pixel Avatar
</td>
<tr>
<td align="center" class="vbmenu_option" ><img src="/forums/images/gixxer/misc/avatar_sample_96.jpg" border="0" />
</td>
<td align="center" class="vbmenu_option"><img src="/forums/images/gixxer/misc/avatar_sample_144.jpg" border="0" />
</td>
</tr>
</table>
</div>
<!-- / forum tools menu -->
It is unclear to me what, if any, plugin they are using. Have you tried asking?