My understanding from pop culture and various moving pictures is that thermoses’ most popular use is for drinking hot things on the go. You unscrew the lid, and it functions as a cup. I have a thermos, and indeed the lid functions quite well as a cup. I enjoy using it at home.

However, a problem occurs to me, in that the cup does tend to get dirty after you’ve drunk something out of it, unless that something be plain water. That’s fine if you’re using the thermos all day in one place. You drink, then you fill the cup back up, you wait for the drink to cool down, and you drink. And if you do decide to save the rest of the drink for later, you can simply wash the cup.

But how are you supposed to keep the cup clean when you’re out doing things? If I have a drink of something hot and yummy during a meeting in one location, and subsequently move to a second, my inclination is to screw the cup back on for storage and transport. But won’t that make a mess? If I have a series of engagements across the day and would like to have a hot drink at various times throughout that day, what do I do with the lidcup all the rest of the time?