SaaS Email Templates - Responsive HTML email templates for SaaS startups
Pistachio Email Templates - Delicious newsletter templates built for automation
Email Template Generator - Email templates for your important relationships
Templates by Email Monster - Hundreds of free, responsive email templates. Pick and edit.
Transactional Email Templates by Postmark - Open source email templates for use in your SaaS app.
BEE Email Templates for Gmail - Beautiful & editable templates right in your Gmail account