Teflon Lined Mug

If you've seen the light and graduated from plain, brewed coffee to lattes and cappuccinos, then you know that milk foam often sticks to the insides of your mug and refuses to expedite its journey into your mouth. So, lets line coffee mugs & tall tumblers with teflon so the foam slides right off and proceeds to intensify the enjoyment of your beverage.

Now, the problems you're going to propose and my answers: 1. If you think there wouldn't be a big demand for this because most people don't put frothy drinks in their personal mugs, you're wrong! More people than you think have espresso machines at home and Starbucks gives a small discount if people bring their own mug. Plus, a teflon coating would be helpful for regular drinks too.

2. As far as safety, if teflon is safe enough to fry stuff on in a pan then it is perfectly safe in your mug. The coffee wouldn't be abrasive enough or sitting in the cup long enough to pick up traces of teflon. Just don't clean it with steel whool.