We went away for a long weekend once, took the porch awning because of the weather, but forgot the poles. I spent the first hour on the site cutting as many nice straight branches off the trees in the woods nearby and lashing up an awning frame with them.
I've also left the cool box with all the food that we couldn't get into the fridge on the driveway next to the car before we left home. I was just about to put it in the back of the car as the last item when a bus came around the corner and I had to move the car in order for the bus to be able to pass. Because the cool box was then hidden behind the caravan and I was a bit flustered by having to move the car so quickly, it remained on the pavement when we drove off. I only realised that I left it there after driving for two hours so I phoned a neighbour who took it into his home for safe keeping. I told him that he could enjoy the contents.