Speaking of ice cube trays, when I visited Japan, one of the hotel room fridges had these neat little bottles, with semicicular depressions on one side. You would fill the bottle with enough water to fill the depressions, freeze, and then shake the resulting ice cubes free. The advantage is the closed bottle helped to keep the ice from subliming and/or absorbing bad odors/tastes from the fridge interior.
I have been unable to locate these since then, even on-line. It appears someone took a patent out on the idea, and since then nobody's been able to sell them. Except for one on-line offering in Australia that I found, but I doubt they would ship to the USA.
Seems to me if someone takes out a patent on a good idea, they should see to it that the idea gets manufactured and sold.