1.) Google Apps :

Google Apps is a service from Google for using custom domain names with several Google products. It features several Web applications with similar functionality to traditional office suites, including: Gmail (email service), Google Calendar, Talk, Docs, iGoogle and Google Sites.

Their are currently two plans out of which one is standard (free) while other is premium (paid). Premium cost for 50$/Year per user while standard plan is free but with less facility.

All basic facilities have been included in Standard plan, so their is no need to go for premium one. It enables you all facility like pop3, mail forwarding, auto reply, filters, etc.

Here is video showing Gmail service for Google Apps

2.) Windows Live Custom Domains (Windows Live Admin Center)

Windows Live Admin Center (earlier Windows Live Custom Domains) is a free service provided by Window Live. It enables users with domain names to change their domain MX record (Mail Server) so that they can enjoy the full features of Windows Live (Hotmail) on their personalised domain.

More better option is that you can provide free sign up link to your members on your website. As hotmail their is no pop3, mail forwarding or like that.

My Suggestion

As it seems to be clearly from my above post that I recommend Google Apps rather then Windows Live Admin Center. I have used both the service and I think Google Apps is more better.

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