Interesting article about ice cubes on the Practically Edible site.
You can learn who invented the ice cube tray, how to get the clearest ice cubes (boil water, keep tray overnight in fridge before putting in freezer).
The cubes may not be perfectly clear so if you are a stickler for such things, you can buy a clear ice cube maker for about $1300.
If the ice cubes from your fridge's ice cube maker are tasting funky, they offer suggestions to try and rememdy that.
They suggest using only aged ice cubes for martinis as they melt slower.
I found the discussion of plastic ice cubes amusing, but that's just me. Who knew you could buy ice cubes that light up.
The site seems UK-based and has a food encyclopedia in seven languages. I never thought so much about ice cubes.