The cheering quieted as the audience tried to catch the new sound: something low and steady and hard to place but undoubtedly familiar. A few people caught on, and let out whoops of delight. The rest were mystified.

"Can you guys work off of that?" asked Stephen, looking at the talent assembled around him. All nodded, puzzled but obliging, and the host turned back to the audience — somehow grinning even more broadly than before.

"That," he announced, "is my baby's heartbeat."

Best idea ever. I would bow down to any rock star who tried to do that in concert. Awesome.