Mailo - Mailo is an email client where you can send and receive emails to and from anyone with an email address.
Really Good Emails - A large collection of good product email design.
HEY - Email at its best, new from Basecamp.
Good Sales Emails - Best sales emails from great companies
Horde - Horde Groupware is a free, enterprise ready, browser based collaboration suite.
Great Email Copy - A dose of emails from around the web.