I was jamming when the sun came out, so I thought let's put on my sunglasses. Grinding at a double j-stick, landing it in all my enthusiasm I thought it was a good idea to give a triple a try. And for some reason my head decided not to move, and as you will probably have guessed already, my ken flew right into my face and knocked my glasses of. Picked them up and saw a one of the pieces of glass had shattered...
You're very lucky nothing got in your eye. I guess there's something to be said for wearing "plastic" glasses when playing kendama.