Nectar’s sonar bottle caps could save $50B in stolen booze

Barslose 20% of their alcohol to overpours and “free” drinks for friends. That amounts to $50 billion per year in booze that mysteriously disappears, making life tough for every pub and restaurant. Nectar wants to solve that mystery with its ultrasound depth-sensing bottle caps that measure how much liquid is left in a bottle by measuring how long it takes a sonar pulse to bounce back. And now it’s bringing real-time pour tracking to beer with its gyroscopic taps. The result is