i make PR buttons as part of my officer responsibilities. they're really cute, and our girls sport them proudly on their purses, bookbags, shirts, etc. the buttons are about 1 1/4 inch in diameter and have sayings like "I (heart) Theta" on them. They're fun to wear in casual settings or even when going out with the girls.
If you'd like, I can send you some! Just let me know