I was catching up on my Shark Tank episodes, and was watching one recording from January, where two fellows were selling Coffee Joulies, small stainless steel ‘coffee beans’ that somehow cooled your hot coffee down quickly to a drinkable temperature, but kept it at that nice warmth for hours.

How? The idea is that the beans contain a ‘secret substance’ that melts at about 140 degrees. Of course, any cold item will warm up while it cools the coffee. Look at ice cubes. But it’s more than that, since taking an object from solid to liquid requires extra heat, and this extra heat lets these Joulies act as sort of a heat battery – taking extra heat form the coffee and cooling it down, then putting that back into the coffee as it in turn cools down.

As soon as I saw the show, I was thinking of a better alternative – why carry stainless steel ‘beans’ around when you could have a cup made of the stuff?

They were coy on the show about what the secret substance was, but it didn’t take long to figure out beeswax, with a melting point of about 145 Fahrenheit, would be perfect for the job.

So, get a stainless steel inner cup, pack it with beeswax, add an insulated outer cup, and you have great way to keep coffee hot – but not too hot (and you need an insulated outer cup – otherwise the coffee will cool down fast, Joulie help or no help).

Great idea, right? I thought so, and so did John Ryan, who patented it over 40 years ago! Check out patent 3,603,106. Or patent 3,995,445 from 1976. Or even patent 20,090,283,533, which somehow got awarded in 2009!

On the bright side, the product is wide open to offer – as these fellows found out by turning it into a bean (which might be their variation so as to get patented, if indeed they plan to).

But the moral of the story is, if the idea seems obvious, it likely was – to somebody else years ago…