At the risk of looking like an ad in the back of the People's Friend, I bought a heated boot a few years ago and it's been the difference between sticking the heating on in the afternoon and not, when I'm at my desk.
If my feet get cold then I'm done, so it keeps my feet warm, which keeps me warm, with the world's thickest cardi on for extra sartorial elegance.
If my feet get cold then I'm done, so it keeps my feet warm, which keeps me warm, with the world's thickest cardi on for extra sartorial elegance.