[Lynne]

Yep, I do this on my site.

In FORUMDISPLAY, find (in two places!):

     <td class="smallfont"><if condition="$show['newthreadlink']"><a href="newthread.php?$session[sessionurl]do=newthread&amp;f=$foruminfo[forumid]" rel="nofollow"><img src="$stylevar[imgdir_button]/newthread.gif" alt="$vbphrase[post_new_thread]" border="0" /></a><else />&nbsp;</if></td>

replace with something like (where x,y,z are the forums to show the other link):

 <td class="smallfont"><if condition="$show['newthreadlink']">
    <!-- added upload page link -->
    <if condition="in_array($foruminfo[forumid], array(x,y,z))">
<a href="otherlink.php" rel="nofollow"><img src="$stylevar[imgdir_button]/otherimage.gif" alt="Other Link" border="0" /></a>
      
    <else />
<a href="newthread.php?$session[sessionurl]do=newthread&amp;f=$foruminfo[forumid]" rel="nofollow"><img src="$stylevar[imgdir_button]/newthread.gif" alt="$vbphrase[post_new_thread]" border="0" /></a>
    </if>  
    <else />&nbsp;</if></td>