When i was eating out today i was getting a bit bored with waiting to eat as it was taking forever. So i started wetting the end of my finger and running it around and around the top of the glass until it started resonating. Only touch the base of the wine glass when you do this as it doesnt work otherwise. each glass is unique in its tone so if you do a few together it makes quite a sound. Everyone joined in in the end as we had a room to ourselves so it didnt matter about the noise.
I always find that Antique glasses work better for this but i cant do this anymore as one by one others seem to smash them all. I always say sarcastically smash as many glasses as you like but please make sure that they are valuable glasses. . I Dont need to ask them anymore as there are none left now.