Balloons: I was once parked, engines running, in an F-15 at Eglin. I don't remember why, probably some exercise, but both engines are turning, and I'm waiting. Bored too.
About 2 miles away, I see a funny, cow-sized black object exit the woods at the field perimeter. It is floating along, bouncing too, like a ghost, a bad special effect from a 1950's movie. About a mile away, I realize it's about 50 toy balloons inside a huge garbage bag. And it is coming straight at me. I cannot move the jet.
100 yards to go, and it is still coming directly at me. The weird thing was that I had been watching it for maybe 40 minutes... the entire time, it was like it was locked on to me. I radiod our ramp rat and said "I gotta shut down." No time to wait for a reply, I kill both engines as the balloon ghost impacts my nose gear. A few moments later, I see it exit to the rear and continue across the field.
In the AF, you are not allowed to crank without a ground crew, a big fire bottle, etc. No way on my own to crank it back up. They had to bring out a tug and drag me back to the ramp area. "What'd you shut down for?" "A big garbage bag of balloons." "Uhhh, OK, whatever." Shot down by 50 cents worth of latex and plastic.
Anyone ever seen one of the ultra-high altitude research balloons launched at the WSMR in Alamogordo at dusk? These are the HUGE silver jobs that float up to 120,000'. They are visible for hundreds of miles, and are so high up that they look like a small moon. At dusk, they are still in direct sunlight. It's a cool sight.