MAPI

AnyMail
Automatically checks your Web-based mail in-box. This program supports Outlook and other MAPI clients
http://www.tntsb.com/

ePrompter
Free email notification software that automatically checks up to eight password protected email accounts.
http://www.eprompter.com/about.htm

MAPInotify
Advanced a 32-bit mail checker utility that can monitor unlimited mailboxes or Microsoft Exchange public folders.
http://www.silmarilsoftware.com/