I was standing on Telegraph in Berkeley, just minding my own business... listening to a band play somewhere nearby and watching the people. I suddenly got the strangest feeling of Deja Vous! I had a strong compulsion to look upward. I slowly tilted my head back. Now, I am pretty tall, about 6'4". Well into my field of vision came something shiny. At first it didn't register, it seemed unreal. But as I looked up I could not deny that there was a stainless steel knife stuck in the tree I was leaning on, about a foot above my head! It had 2 3 inch blades, one a straight razor style blade and the other a quick open sharp pointy one. I looked at it for about 5 minutes. Finally I resolved to take the knife for myself. The odds that someone would be back for it seemed remote. I stretched out my hand to pluck the knife from it's spot above my head. As my fingers wrapped around the cold metal, a homeless man stepped very close to me and said in a low voice

"Is that yours?"
"It is now." I said.
"You better be careful- well, oh it's too late. Your finger prints are all over it."
"What? Is this yours?"
"No, not mine. But there's always a reason when you find something like that."

THen he quickly walked away.

I took the knife I found and washed it well, then boiled it for a couple of hours just for good measure.
I was a little paranoid for a while about the knife, but now I use it for good and it is always with me.