There is also the Cleaner module.
 
Nancy
 
Injustice anywhere is a threat to justice everywhere. -- Dr. Martin L. King, Jr.

From: sivaji j.g

> In settings.php, you can define how long a cookie is good for.

This is fine but when the PHP garbage collection is not in place or
misconfigured it won't work as expected. Well there is a module for
that http://drupal.org/project/session_expire