At park outside main train station. He was mostly talking to himself, but sometimes he would address people at a nearby bench. They all knew him. Becoming quiet, he read a book and, glancing over, I noticed that it had black and white illustrations. Then he took a couple of minutes to draw something. It turned out to be a sign, "PLEASE YOU [three drawn coins of 20, 10 and 1 koruna] THANK YOU!!!"
To get rid of extra korunas, I had just gone shopping for grocery. I bought two cans of goulash, some canned fish, dried beef sticks, a jar of coffee, etc., all for less than I'd have paid in Germany.
Though I only had 12 korunas left to give him, dude was happy to sell me his little sign. "Bye, bye!" He shouted quite cheerfully as he sauntered away.