I think all the sharks liked the ice cream idea.
if it takes 5 Joulies for a 16oz. cup of coffee
and it takes 30-50 gallons to fill a bathtub halfway (let's go with 30)
it would take 1,200 Joulies... or $12,000 @ 5 for $50...
I didn't think the Joulies would be a chocking hazard, they'd just be annoying if they slide around. Kinda like having ice at the end of a drink, except a lot bigger, solid, and the beverage is hot.
As per wiki
Quote:
A similar concept using phase change materials, but integrated into the walls and bottom of a cup, had been invented by the Fraunhofer Institute for Building Physics two years earlier.
Probably not as effective but I'd much rather have them built into the cup.