jetMailMonitor 6.0 is a E-Mail checking utility that conveniently notifies you when new messages arrive on your POP3 mail server.
It supports up to 50 e-mail accounts and supports Exchange, Netscape, Outlook97, Internet Mail, Outlook Express by default. You can register your own mail client program, too.
http://www.cowonamerica.com/products/jetmailmonitor/