To do it next to thread tools like currently in the demo (March 2011):
Edit SHOWTHREAD template...
FIND the code below and ADD the code in
RED
Code:
<td class="tcat" width="100%">
<div class="smallfont">
<if condition="$show['firstunreadlink']">
<a href="$firstunread"><img class="inlineimg" src="$stylevar[imgdir_button]/firstnew.gif" alt="$vbphrase[view_first_unread]" border="0" /></a>
<a href="$firstunread"><strong>$vbphrase[view_first_unread]</strong></a>
</if>
</div>
</td>
<td class="vbmenu_control" id="threadshare" nowrap="nowrap">
------TWITTER CODE HERE-----
</td>
<td class="vbmenu_control" id="threadtools" nowrap="nowrap">
<a href="$show[nojs_link]#goto_threadtools"<if condition="is_browser('ie')"> accesskey="3"</if>>$vbphrase[thread_tools]</a>
<if condition="$show['popups']"><script type="text/javascript"> vbmenu_register("threadtools"); </script></if>
</td>