You stand at the counter of your local muffin spot. It’s the sort of day where it’s only 9 a.m. and your neck is already sweating. Though an admitted caffeine fiend, of course you don’t want hot coffee; you want iced. Or do you? No, you do not. You want iced tea, the only drink suitable for these circumstances. There is a temperature window where iced coffee is optimal. We’ll call it 67 to 80 degrees.