The economy and government finances of Detroit, Michigan are in awful condition. Fire departments in particular are struggling to address the city's 11,000-12,000 annual fires with little money. There is no centralized fire alert system. Or, rather, there's no modern one. But clever firefighters have found ways to learn about fires so that they can respond quickly.
One common method used in many firehouses throughout the city is a soda can filled with coins. Firefighters balance the can on their firehouse office printer. When a fire alert is faxed in, the paper knocks the can off the printer, making a loud noise. Then firefighters then know that it's time to check the printer and move out.
-via Gizmodo