Well, maybe not the worst, but probably not the best either... Years ago I was coming from a bar, pretty drunk as usual, heading home. Suddenly I felt the urge to take a dump. I could've easily saved it to home, but instead I got this magnificent idea to climb to a roof of the next apartment house (like 10 stories high) and do it there. Luck was on my side (but not on the resident who lived below, I might imagine) as I found a small ventilation pipe thing sticking up from the roof. There was a small "hat" on it, which I removed and then carefully aimed my...grenades in a hole. My luck continued, I hit the target and the bombs were pretty solid (I had no paper with me). I put the hat back on, climb down the ladders, didn't fall down and kill myself and went to bed. Next day when I suddenly recalled all this, I started thinking...maybe it was someone's kitchen ventilation? Let's all hope so.