Google’s Gmail system is the best email system available on the internet. The fact that it is free just makes it that much better. We have been advising clients to use Gmail as their email provider for months as it gives them the flexibility that they want from an email provider. Our ubertor.com email runs on Gmail’s hosted program. That just shows you how great it is as you can mask the email address so that your clients and potential clients see your domain name, and not the gmail.com addresss.
Google has just taken it up another notch by launching Gmail For Mobile. More details here and here.