It is possible, but you'll have to modify your pligg files. There is no module for this, as far as I know.
1. open libs/link.php
2. find this string:
PHP Code:
$smarty->assign('story_url', $this->get_internal_url());
3. below that string, add the following code:
PHP Code:
$previd = $db->get_var("SELECT link_title_url FROM ".table_links." WHERE link_status = 'published' AND link_id < $this->id ORDER BY link_id DESC LIMIT 1");
$nextid = $db->get_var("SELECT link_title_url FROM ".table_links." WHERE link_status = 'published' AND link_id > $this->id ORDER BY link_id ASC LIMIT 1");
$smarty->assign('story_prev_url', getmyurl("storytitle", $previd));
$smarty->assign('story_next_url', getmyurl("storytitle", $nextid));
4. open link_summary.tpl in your templates folder
5. insert this code where you want the prev/next links to be:
Code:
<a href="{$story_prev_url}">Previous story</a><a href="{$story_next_url}">Next story</a>