Email

Clients

Microsoft Outlook - Email client from Microsoft, available as a part of the Microsoft Office suite (F)

Thunderbird - Formerly developed by the Mozilla foundation (F)

Providers

1and1 - Email hosting from full service web provider  

atmail - Linux-based email (FT)

Gmail - Email service provided by Google for business (web-based) (FT)

Rackspace - Email and hosting service provided by rackspace