Lob - A simple API to integrate print & mail solutions into your applications.
Revue - The easiest way to create and send a curated newsletter
Click2Mail - Mail outsourcing on-demand.
Substack - Substack makes it simple for a writer to start an email newsletter that makes money from subscriptions.
Sendoso - Sendoso’s B2B engagement platform helps companies accelerate sales and retain customers with gifts and rewards.
Discover by Revue - A directory of personal newsletters