I know there are many modules like "service links" or social bookmarking services like addthis/sharethis etc. but I just want to have a small block on top-right side for my users with a facebook account.
$fb_title = drupal_get_title();
$fb_url = "http://".$_SERVER[HTTP_HOST].$_SERVER[REQUEST_URI];
$fb_url = rawurlencode($fb_url);
$fb_title = rawurlencode($fb_title);
$fb_url = "http://www.facebook.com/sharer.php?u=$fb_url&t=$fb_title";
echo << Share this page on Facebook! hrd;
?>