Adding to the stories I've heard...
A friend of mine who went to Java, looking for a powerful keris which can stand on its end when commanded. So as he was talking loudly about keris at a warung kopi, one of them whom was showing him a small old keris. Suddenly, a man appears before them and asked "..., would you like to see the keris stand?" (in Bahasa Indonesia). Both of them replied "Yes of course."
Then the man asked to put the keris flat on top of the table and commanded the keris to stand on its tip. To their surprise, it did stood up... then he picked it up and hand over to one of them.
He then, looked at a spoon, next to them and asked them to look. He then commanded it to stand. The spoon did stood vertically. The two of them looked at each other in awe... Then the man asked "Do you want to learn the art or do you still want a powerful keris which can stand."
While they were thinking... about what the man said, the man had left the warung...
That's all I have to say... the moral of the story... hmmm... I don't know?
You decide...