Hands-on with Mr. Postman, a smart mailbox that links your inbox to your letterbox

Sometimes, even the oldest cliches can serve as inspiration. Take the dog and the letter carrier, for instance: when Manuel Masri first moved to the United States, he was surprised to find his canine companion obsessed with the mailman. Every delivery became an event, anticipation for a 4pm delivery and an excited pooch -- but the K-9 notification system only worked when he was at home. His solution? Mr. Postman, a mailbox that knows when to expect your mail, notifies you when it arrives and locks after delivery.

Masri's smart mailbox falls into that growing category of the "internet of things," something that links typically disconnected physical objects with each other and your digital world. It also happens to be one of Engadget Expand's Insert Coin semi-finalists. We dropped by the company's show booth to see the project's take on the future of mail delivery.

At first glance, Mr. Postman just looks like an extra-wide mailbox, differing from your standard letterbox only by the breadth of its ten-inch mouth. Look a little closer, however, and you'll find a wealth of technological goodies: solar panels, an automatic locking system and a WiFi-equipped Rasberry Pi brain (although we're told the final product will use a Spark Devices Arduino). These components allow Mr.Postman to be a smarter, more secure mailbox. Using a companion app, users can check the status of their mail delivery, remotely lock or unlock the box and even dole out virtual keys to allow neighbors to pick up mail in the absence. Don't have anybody to look after your mail while on vacation? Don't worry about it: Mr. Postman can automatically learn your mail carrier's habits, unlocking 30 minutes before his typical arrival and securing the contents after delivery.

It's not just a way to upgrade your curb-side mail deliveries (it actually comes as a kit, complete with mailbox,) Masri tells us that there's a really good opportunity to integrate the technology into community mailboxes. This would mean your shiny new apartment could come complete with a smart mailbox. Masri also explained that the team has experimented with a variety of different sensors that would even let you see what packages have arrived. But, sadly, a mixture of USPS requirements, and low light (it's dark inside them boxes) make this impractical. He did, however, go on to confirm that an API would allow USPS deliveries to hook into the app, and let users know of their arrival that way.

James Trew contributed to this post.