Have an irresistible urge to correct other people's grammar but don't want to be rude? Did someone take away the marker that you used to cover up all those errant apostrophes?
This mug, emblazoned with the phrase " I am silently judging your grammar", is for you. Get your point across without ever saying a single word. Take a sip, while wordlessly raising a single eyebrow, and watch them squirm.