Picture: Some big ugly flaw on my sensor after the camera hits the ground.

So there I am, standing along the bank of the Eel River in Humboldt County. I was close to wrapping up my trip along that section of the coast, and was shooting the Avenue of the Giants. My camera was on the tripod when I went to change lenses. My camera bag was a couple feet away, so I dismounted the lens that was attached to the body, and carried it to my camera bag. As I reached my bag, I heard behind me the sickening sound of a whack-thud. The wind had blown over the tripod and camera body, which had a gapping hole where a lens should have been attached. The Gods had been kind in that the camera fell with the lens mount face up, and the back of my camera taking the full force of the impact with the dirty, dusty, gravel-laiden ground. With my heart wrapped around my feet, and my stomach near my throat, I walked over and looked down at the camera. I could see the mirror appeared half open and could see the sensor behind it. I was sure my trip just ended in that moment.
There was only one thing to do; Test the camera. I put the lens on, turned on the camera, said a prayer, and clicked the shutter. The camera took the picture, but what showed up on my preview LCD panel was the big black disgusting looking flaw that you see above. My camera was toast. I was sure of it. Nonetheless, I took the camera back to my truck, and began to clean the sensor to see just how bad the damage was. What transpired was that after the first cleaning, the big black ugly flaw had gone away, but some spots remained. So I then proceeded to swab the sensor, and eventually everything was cleaned and working normally.
When I uploaded this CF card to my laptop, I realized what this big black flaw had been. While my camera had been laying on the ground, apparently a hatch fly had flown into the camera. So what I first thought was massive damage to my camera just turned out to be some very unplanned, extreme close-up insect photography.