Iced Venti Coffee Cozy

So folks, what do you think? Since I work at a Starbucks and spend quite a bit of time knitting; when I'm not putting little cardboard sleeves on cups of coffee that is, it was a natural to link the two. Wonder how much cardboard people would save if they just used little knit sleeves each day. Hey does anybody think I could sell one or two of these things? Maybe if I charged a buck or so for them?