Does any supermarket sell them?

Is this a gap in the market?

If they're spherical they're not a cube 😆
I use the bags that you fill with water and freeze.

http://www.amazon.co.uk/gp/aw/d/B00H...V0L&ref=plSrch

Amazon carries them.

People buy icecubes?

You can buy moulds for making them anyway - I've seen them turned out in cocktail bars.

you could just use a cake pop mould if you wanted round ones.

Sadly they do, supermarkets have bags of them in the freezers.
What I find more strange is the lazy b's who but grated cheese

spherical ice cubes? now there's a dichotomy

I have seen them but I can't remember where. They were silicon cake moulds, for making cake lollies but could be used as an Ice tray. I think it may have been in Dunelm.

http://www.dunelm.com/product/silico...hTerm=silicone

Can't have been Dunelm as these are not the ones I saw. The ones I looked at were 2 halves that click sealed together in a tray and they a large opening at the top so you could fill the mould.

I'll keep looking