Several scenes in Coffee Crash are set at the Grande Hotel in Águas de São Pedro, Brazil, a real hotel. The Coffee Crash plot includes tracking of a guest's key card accesses to door locks in the hotel.

In the non-fiction world, a hotel's door lock system may or may not have such capability. Some newer door lock systems use wireless radio-frequency (RF)technologies such as ZigBee that enables each lock to communicate with a central server. Saflok is an example of manufacturer supplying hotels with these systems.

I don't know whether or not the Grande Hotel actually uses a system with that capability. Nevertheless, the next time you check in at a hotel, you might think twice about where and when you use your key card. Big Brother could be tracking you.