Here’s something I once posted in a newsgroup.
Last night, I was practicing with some water-colors and I painted a series of concentric black and white circles, kind of like an archery target. Later, while I was asleep, I dreamt I was in a store. I saw that there were bows and arrows for sale, and I realized I had a consuming desire to practice archery. I picked out a bow, but I couldn’t find any arrows. Then I realized that they were haphazardly scattered about the floor, intermixed with long-handled paintbrushes. The arrows were missing feathers, and then other difficulties began to intervene, until I despaired of ever putting to together a decent archery set.
Then I woke up and realized I wasn’t interested in archery at all; I wanted to paint.
I had intended to end this story with the Zen saying "The skilled archer does not aim for the center of the target,” but I wanted to look it up in Yahoo to see if I could find the original reference. The first Yahoo hit I found was a newsgroup thread where I had quoted it earlier without reference. And if that's not some kind of koan, I don't know what is.