If you have some other machine on which to install a simple daemon you could just use one of these for $35 https://www.sparkfun.com/products/10822 https://www.

If you have some other machine on which to install a simple daemon you could just use one of these for $35 https://www.sparkfun.com/products/10822 https://www.sparkfun.com/products/10822 It's a low-power WiFi client with a bunch of IO that you can configure to periodically do a TCP call to some server you own to get orders on what to do. If you don't mind having it always on you can invert that and have the server initiate the call. You lose the ultra-low power usage in that case. I've been evaluating it to create sensor/actuator networks and it's been great so far. It also has a serial port so your display example would work as well. It's amazing that a full computer (the raspberrypi) can come so close to this on price but the raspberry is an energy guzzler compared to this and for anything you want to battery power that's a big deal.