Roundcube - Web-based IMAP email client
SendOut - Affordable email marketing for bloggers and influencers
HEY - Email at its best, new from Basecamp.
Mailblast - Email marketing on a budget using Amazon SES
Mailo - Mailo is an email client where you can send and receive emails to and from anyone with an email address.
rasa.io - Get more from your email list.