Ice Coffee Emergency Button
We have an iced coffee keg from Joyride Cofee filled with Stumptown cold-brew. Everyone enjoys it so much that we run out fairly quickly. To inform our facilities team when a keg is empty, I built an "Coffee emergency button" that files a JIRA to let them know it needs attention.
It is built with a SparkCore device that is on our wifi network, and a cron job that queries it once per minute to poll the status.