Re:Own email server (Score 1)

Actually, many ISP's do not allow it:

Optimum Online:

        Users may not run any type of server on the system. This includes but is not limited to FTP, IRC, SMTP, POP, HTTP, SOCKS, SQUID, DNS or any multi-user forums;

Verizon:

You also may not exceed the bandwidth usage limitations that Verizon may establish from time to time for the Service, or use the Service to host any type of server.

Comcast:

use or run dedicated, stand-alone equipment or servers from the Premises that provide network
content or any other services to anyone outside of your Premises local area network (“Premises
LAN”), also commonly referred to as public services or servers. Examples of prohibited
equipment and servers include, but are not limited to, email, Web hosting, file sharing, and proxy
services and servers;