Absolutely minimal intercom system. Create a "Signal" or join someone elses, then use quick communication buttons in situations where it might be useful!
Like, strictly hypothetically, when your wife yells up at you in your mancave that "TEA IS READY", and your dog starts barking like crazy until you come down - now, she can simply press the "TEA IS READY" button, you can respond with the "COMING" button, and no barking will ensue!