When empty,the glass sends an electronic cry for more beer from the table to waiters equipped with hand-held computers on frequencies similar to those used by mobile phones.

• 当酒杯空了的时候，它就会从顾客坐的桌子发出电子提示声提醒服务生需要添酒了，而服务生手中则拿着可以接收频率的掌中电脑，就和手机发出频率的道理差不多。