Ever since my "tiny $20 tablet" project (see my Open-Source Classroom column in the March 2015 issue), I've been looking for more and more cool things to do with cheap Android devices. Although the few obvious ones like XBMC or Plex remotes work well, I've recently found that having Android devices around the house means I can gain back an old-school ability that went out of style in the late 1980s—namely, an intercom system.

If you remember the big white boxes screwed to the wall in the garage and basement so you could talk to the person in the kitchen about making sandwiches, you know exactly what I mean. With multiple Android devices around the house, it means I can send an audible message quickly without the need to call or text.

There are several great intercom apps in the Google Play store, like "Intercom for Android", "Intercom for Android" (yes, more than one!), "Tikl" and so on. Each has its own set of advantages and disadvantages. Some work well over great distance by using the Internet, and some work with an ad hoc Wi-Fi connection between rooms. Whatever your instant communication needs, the intercom idea is one worth exploring, especially if you have multiple Android devices around your house. Download a few apps today, and let me know when that sandwich is done!