Google Apps for Business is the way to go. $5 a month per user and it's their policy that you to have only one account. It functions under one domain/email address but you can have an unlimited amount I have three domains and several sub-domains from GoDaddy. One of my sites is on WordPress, one is on Google Sites, and one is on Blogger. All my domains are registered at GoDaddy and the WordPress site is hosted at GoDaddy, and a few sub-domains are on Tumblr. So, yeah, you can be all over the internet and it requires only one primary domain. You get the full benefits of the Google Webmaster and Google Analytics features and unbelievably much more, all for $5. By the way, Google doesn't register or host domains.
Right now I'm checking out the possibilities of how I can integrate S-Drive with my sites and blogs. Don't think I'll have a problem. Great job you all...CoffeeCup.com Rocks!
Google Apps: http://youtu.be/15zSL5infoc

Right now CoffeeCup registered domains have access to three DNS record types: A, CNAME & MX. Access to those type records will not let us create deliverable email at a 3rd party email service.

If we also had access to create TXT record types we would be able to set up SPF and DKIM records...protecting the email accounts from phishing and spammers.

Can you add TXT to the DNS record types we can create?

What you need to do is a file upload domain verification process. Upload that file to the root folder of your server to complete the verification process.