Tea Bag Notch, in action! - I order tea from Starbucks and they often double up the cups in order to keep the tea bag tag from falling into the hot water. Perplexed by this waste of an extra cup, I considered many solutions but settled on a spiral notch punched into the cardboard cup holder to anchor the tea bag string. This is a cheap, simple solution that would dramatically reduce cup usage without adding to costs in a significant way. It's also really easy to use. I promise.
Sketches of Problem and Various Solutions - I was inspired by both the tension assembly for a sewing machine, and the handy notch on a standard spool of thread. I originally thought I might be able to punch a notch into the cup itself, but found it dangerous given the hot water involved. Creating a notch in the protective cardboard cup holder encourages safe use with all of the same benefits.