Floated this cold-hat idea before as a commercial climate-combat accessory blockbuster hit. I do a mock version of it all the time in summer - a flexible ice pack in the hat separated by a cloth from your head. It works pretty well. It may be possible to do it as usb chargeable thing.

Now i'm thinking it could have a role in elite sport. The Boxing Day Test in Melbourne is a big deal in cricket.

The forecast temp for Dec 26 is 39C. That's actually quite dangerous weather to be playing a physical sport in. Considering the extremist lockdown lengths Vic.Gov went to keep everyone safe during the Covid reign of terror, extreme heat is probably more dangerous for a younger demographic, including players, certainly, but also the 90 000 spectators expected to turn up.

One way to keep us safe would be the Frigo-hat. There'd be a question as to whether that provided an unfair advantage, but for safety concerns alone it should be introduced. Cricketers already wear helmets to protect their heads (introduced about 40 years ago), now it's time to chill that helmet.