What do you expect from e-mail system?

Apart from the regular e-mail handling, the e-mail system should provide some additional tools to help the user manage his daily work better. Apart from accessing his e-mails, the additional tools one may expect are:
 

1. Management of calendars
2. Management of contacts
3. Management of content sharing
4. Instant messaging
5. Collaboration tools, etc.

 
The other facilities which the user may find very useful are:
 

1. Facility for better management of ever-growing inboxes effectively
2. Facility for full-text search on e-mails
3. Facility for e-mail filtering and sorting
4. Built-in protection for Anti-spam and Antivirus
5. Scalability for better performance
6. Tools for better mail-administration, etc.

 
Some of the popular e-mail applications are IBM's Lotus Notes, Netscape Mail, Microsoft's Exchange, etc.