Square Heineken bottles. Beer bottles that double as bricks to build houses in impoverished countries. Unfortunately, the bottles never saw the market.
https://s3-us-west-1.amazonaws.com/h..._heineken1.jpg
https://s3-us-west-1.amazonaws.com/h..._heineken2.jpg
https://s3-us-west-1.amazonaws.com/h..._heineken3.jpg
https://s3-us-west-1.amazonaws.com/h..._heineken4.jpg
More:
https://www.smithsonianmag.com/arts-...uare-62138490/
Previously:
https://www.homemadetools.net/forum/...978#post120102
https://www.homemadetools.net/forum/...573#post110975
https://www.homemadetools.net/forum/...951#post119905