The beagle board, and atom boards are inexpensive enough, I would consider them the down side. A netbook at Walmart isn’t that much more expensive, after you consider how much more you get I’d consider the ongoing expense of maintaining telephone service the downside. Assuming all parties have a computer, and internet access, the same information could be shared with Google Docs, with no additional costs. Having said that I appreciate Achu sharing his project,and HAD for featuring it, for the stuff I can learn from it. Finally my free installation of Eagle reports that the file untitled.sch contains invalid data.

While Asterisk may be a better solution for PBX-style functionality or database interface, this could be a fantastic way to interface with a uC project remotely.

Say, for example, you wanted to remotely launch a model rocket and the user could dial the passcode or change options using their mobile phone. If the passcode is entered incorrectly, the user is sent through an endless series of automated option menus in a variety of languages until they hang up :D