HappySend is a tool that makes it easy to send wishes to lots of people through short text messages.
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MailHole runs a super simple SMTP server which catches any message sent to it, and manages them through a REST API and a web interface. Run mailhole, set your favourite app to deliver to smtp://127.0.0.1:1025 instead of your default SMTP server, then check out http://127.0.0.1:1080 to see the mail that's arrived so far.
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