ShareMail 4.7.1   
by LavaSoftware   

One email box + ShareMail = email service for your entire network.

ShareMail can expand ONE email account to several internal mailbox. It acts also as a local email server for intranet. Very suitable for small business. No domain needed.

Features:
Compatible with Win9x/WinNT
Auto recv and send mail
Support alias mailbox
Email broadcasting
Support DUN
NT Service
POP3 Proxy
Refuse email spam
Log
Email backup
Firewall/Proxy support
Remote control
Inner mail exchange
Maillist support
Priority support

Sharemail can support more than 100 mailboxes. The Free version only support 5 mailboxes. For more mailboxes, register the software.