A lad I knew came out with something stupid on a regular basis.
Him and his wife had been on holiday and had flaming sambucas for the first time. Upon their return he thought he'd replicate the flaming part of the drink - on his pint of lager. No matter how he tried he couldn't light it despite his insistance that it should ignite as it contained alcohol.
One evening, around dusk, he found a guy who'd been beaten up at the side of the river. He dialled 999 and reported it. It was quite a way from the road and the police helicopter had to guide the policeman and ambulance men to the spot. There were fisherman and walkers on the riverbank all along the area he was in so in order to quickly identify his position they asked if he could shine his bicycle light up in the air so they tell him from the others. He told us how he struggled to prop his bike with the front wheel pointing up - he finally managed to do it using branches and bits of vine. When we asked him why he simply didn't unclip the light and lay it on the floor pointing skywards he just blinked a lot.
We used to stand chatting outside the pub after it had shut. He had gone to the toilet as we shuffled out. There was a massive pile of dog shit in the pavement and, without anyone saying anything, we stood around it. As he arrive we shuffled around and opened up a gap in the circle - just where the dog turd was. He stepped straight in it. We were pissing ourselves, as you would, and he just said 'I knew it was there. If I'd stepped over it you'd have all started crying so I just did it to keep you happy'