(I come from a family of political button collectors. My grandfather did it, my parents did it separately and together, and I have two bags of them in my bottom dresser drawer. No, I haven't found a good way to display them in my small apartment.)
I have a lot of ones I love [no nukes/no cows!], but I do think this one's my favorite:
Choice in Everything.
(I know life's never that simple, but still....)
P.S. We sent a letter to PKD. Well, Co calls it a letter, I call it a short email reminder. But hopefully we'll hear from him soon.