Imagine if Yoda from Star Wars was speaking. What would he say when the Dark Side was stressing you out? "Calm you must keep and carry on you will, hmmm?" of course! (It really helps if you try and say that in a Yoda voice!)
10oz white ceramic coffee mug with Yoda's version of the slogan printed on both sides. The mug is both microwave and dishwasher safe, though handwashing will increase the lifetime of the print.