Manhora is the Japanese practice of painting manhole covers, which is done in the belief that what lies beneath should be aesthetically appreciated. 

The Manhora Brewery, Inc. began when a group of workers got tired of drinking the beers of the superbreweries - which were the only available at the time - and so decided to set up their own, hidden in the safety of an underground cave in the mountains just outside Tokyo.

To maintain their secrecy they used the bottles of the superbrewies, but used a distinguisable bottecap to set them apart. This bottlecap followed the designs, and principle of the Manhora art - to appreciate what lies beneath.