Regex

I'm trying to come up with a regular expression that will match the TL and Second Level domain names in someone's email address ONLY. So, say someone's address is "joe@relay.mail.someserver.pacbell.net", I need to match ONLY pacbell.net. It shouldn't matter what the address looks like, I'm looking for any number of digits, a dot, any number of digits, and the end of the line. The closest thing I can come up with is /\@.+?(.+\..+)?$/, but, as you can guess, that matches everything except the very first character. Can anyone help me with this? Thanks