Hey i am looking for a decent email system that i can use on the new website i am getting together. I need a Email system that i can use to allow members at my site to setup a email address with my domain name. Something similar to www.hivemail.com but free. thanks.

Google?

I second Google.
http://www.google.com/a/help/intl/en/admins/tour.html

There is also squirrel mail which is highly mature with a lot of third party plugins.

http://www.squirrelmail.org/