Lo del coche era más bien una respuesta para mandrake88.
Mira, he encontrado un MOD que quizá te puede dar la idea de cómo hacer lo que quieres.
Es para otros redes sociales pero como es tan simple posiblemente adaptando el código de los enlaces lo puedes convertir en lo que buscas.
Código:
##############################################################
## MOD Title: Digg, Del.icio.us & Slashdot Mod
## MOD Author: Cobby < [email protected] > (Cobby Drost) N/A
## MOD Author: HoundoftheB < [email protected] > (Brad Bolman) N/A
## MOD Description: This mod adds a Digg, Slashdot, and Del.icio.us Links into your topics so users can promote your posts.
## MOD Version: 1.0.1
##
## Installation Level: Easy
## Installation Time: 3 minutes
## Files To Edit: templates/subSilver/viewtopic_body.tpl
## Included Files: N/A
## License: http://opensource.org/licenses/gpl-license.php GNU General Public License v2
##############################################################
## For security purposes, please check: http://www.phpbb.com/mods/
## for the latest version of this MOD. Although MODs are checked
## before being allowed in the MODs Database there is no guarantee
## that there are no security problems within the MOD. No support
## will be given for MODs not found within the MODs Database which
## can be found at http://www.phpbb.com/mods/
##############################################################
## Author Notes:
##
## Digg: http://www.digg.com
## Slashdot: http://slashdot.org/
## Del.icio.us: http://del.icio.us
##
## Popular sites where users choose the news that makes it to the front page(s).
##
## Demo: http://www.hostingforum.ca/viewtopic.70034.html (look on the left under user)
##############################################################
## MOD History:
##
## 2006-12-03 - Version 1.0.0
## - First release
##
## 2006-12-04 - Version 1.0.1
## - Second release, fixed some errors stopping easymod from installing correctly
##
##############################################################
## Before Adding This MOD To Your Forum, You Should Back Up All Files Related To This MOD
##############################################################
#
#-----[ OPEN ]------------------------------------------
#
templates/subSilver/viewtopic_body.tpl
#
#-----[ FIND ]------------------------------------------
#
<td width="150" align="left" valign="top" class="{postrow.ROW_CLASS}">
#
#-----[ IN-LINE FIND ]------------------------------------------
#
{postrow.POSTER_FROM}</span><br />
#
#-----[ IN-LINE AFTER, ADD ]------------------------------------------
#
<span class="topictitle"><a href="http://digg.com/submit?phase=2&url=http://www.YOUR_URL/{U_VIEW_TOPIC}&title={TOPIC_TITLE_FULL}">Digg It</a><br /><span class="topictitle"><a href="http://del.icio.us/post?url=http://www.YOUR_URL/{U_VIEW_TOPIC}&title={TOPIC_TITLE_FULL}">Del.icio.us</a> <br /><span class="topictitle"><a href="javascript:location.href='http://slashdot.org/bookmark.pl?url='+encodeURIComponent(location.href)+'&title='+encodeURIComponent(document.title)"></a><a href="javascript:location.href='http://slashdot.org/bookmark.pl?url='+encodeURIComponent(location.href)+'&title='+encodeURIComponent(document.title)">Slashdot It!</a>
#
#-----[ SAVE/CLOSE ALL FILES ]------------------------------------------
#
# EoM