CSCatchAll
CSCatchAll adds a much-needed feature to MS Exchange Server 2000 and 2003: A catch-all mailbox that receives all mail originally addressed to recipients that are not in your active directory. There is zero configuration of CSCatchAll necessary - just install it and add a "catchall@yourdomain.com" email address to any of your users in the active directory. That user then receives all misaddressed email.