HEY - Email at its best, new from Basecamp.
Horde - Horde Groupware is a free, enterprise ready, browser based collaboration suite.
Roundcube - Web-based IMAP email client
InstAddr - Disposable email address application.
ProtonMail - Secure email with absolutely no compromises. Get your free encrypted email account today.
Soverin - Soverin is the honest email service that doesn’t sell your data.