Let's say you have some static landing pages on S3, and you want a contact form. How would you do it? Normally you'd have a PHP/python/perl/ruby/node/whatever

Let's say you have some static landing pages on S3, and you want a contact form. How would you do it? Normally you'd have a PHP/python/perl/ruby/node/whatever script listening on the server for an HTTP POST (or AJAX request, or RPC, or websocket, or whatever) that would send the mail for you. But this won't work here because S3. Your first attempt at solving this will probably be to turn to Mandrill/Mailgun/Postmark/whatever, most of which have some easy way to send an email from javascript, but all of which have some secret API key you need to keep secret. Again, this won't work because S3. The trick is to find someone who'll run a server for you that will accept messages over an HTTP interface and pass them along to a designated email address. And apparently Squaresend will do this, which is honestly pretty nice if you just want a contact form on your S3 hosted website (which is not that strange a need!).