PMSL, thats classic.
One that springs to mind was when i used to be work for a platering company and we were doing work above a bakery, because the bakery was quite old they had their toilet which was a portaloo outsde. My bosss told me go out from the house and tell my mate i was going for a s**t and hid in the van, then my boss said to my mate 'hey, Gareth's gone in the portabog, go and push it over while he's in it so down he goes to the portabog (me watching him all the time) and i think he backs out of pushing it over, instead he just gives it one hell of a shake around! I will never ever forget the shriek that came from the potaloo which belonged to the old woman who worked in the bakery! His face was so funny when he realised that was too high pitched to be me and we all just legged it in different directions with tears running down our faces! When i casually walked back by 5 minutes later, the old woman was there asking some passer-by if she had seen some yobs going by coz they had shaken the portoloo. Of course this sent me off again but luckily not right in front of her!
This sounds equally as funny KP, pmsl.