Sure, Google Calendar is helpful, but ultimately it's on you to get yourself to that meeting. Wouldn't it be nice if the utility could handle some of the to-do list itself? Hack A Day scoped out an example of it doing just that, after a home owner named Shane posted a video of his DIY system that uses Calendar to control his heater. First, he connected a USB-powered mbed microcontroller with an ARM Cortex M3 processor to the internet via an Ethernet cable. As it happens, the mbed also has a temperature controller and solid state relay for turning the heater on and off. On the software side, he took advantage of a feature in the Google API that let him sync the mbed's network time, with the mbed able to "see" in advance what temp changes are scheduled on the calendar. In other words, if turning on the heater is on the schedule, the mbed system knows it and makes it happen. In a brilliant act of disaster prevention, Shane also tweaked the on-board temperature controller to not go above a certain number of degrees. For more technical details, check out the video below and the photos at the source link.