The next time you are drinking some beers with your friend and step away for a second, don’t forget to turn on the Beer Burglar Alarm, it will make the “so called friends” don’t finish your beer.
Basically you attach the alarm system to a glass, and since it has a proximity sensor it will make the (sound) alarm go on if anyone tries to drink the beer.
The “mafia” voice keeps even the most determined beer burglars at bay.
It costs £5 (approximately $10).
PS – replace beer with any other beverage.