An inspirational tribute to the Boy Who Lived, this mug bears only five words in all. On one side, beneath the famous circular glasses and lightning bolt, is the word "always," which both signifies the duration of the Harry Potter fandom, and of course, references Severus Snape's pledge to the length of time he will love Lily. ("After all this time?" "Always.")
On the other side of the mug is another small phrase which recurs twice in Deathly Hallows: "Until the very end."
The first instance this appears is in Rowling's dedication of the book: "...and to you, if you have stuck with Harry until the very end." And the second time we see it is just before Harry's surrender to Voldemort, during the (emotional, anyone?) Resurrection Stone scene: “You'll stay with me?' 'Until the very end,' said James.” (c) J.K.R.
All in all, I would say these may be the five most significant words in all of Potter. :)
Beside the handle I have painted an owl. And that goes without saying.
All of my work is done with heat-set ceramic paint, and will do very well with dishwashers and the ordinary passage of time. I would, however, recommend against the use of strong abrasives.