Emoze is a free push e-mail and PIM service for mobile devices. Using emoze, users with supported mobile devices can automatically receive emails in real time, and synchronize contacts and calendar free of charge, paying only for data charged by the mobile operator. Some features are:

Real time wireless push email
Wireless email, calendar, and contact synchronization with full Outlook(r)-like functionality
Powerful compression that saves data transfer costs
Support for a wide range of devices - including Symbian Series 60 and Microsoft Windows mobile 2003 and 5.0

EMoze