It´s possible close the session (make logout) when user close the web browser?

It´s possible close the session (make logout) when user close the web browser? And, it´s possible that when user make login in other host, the first session in the other host close. No virus found in this outgoing message. Checked by AVG. Version: 7.5.524 / Virus Database: 269.23.7/1408 - Release Date: 30/04/2008 18:10