Not any one thing, but a combination of things I don't think many people have.
An earthquake (several actually), a tsunami, tornadoes, hurricanes, wildfires, riots, and war. Never shot at anyone or got shot at though, thank God. I've flown a helicopter and SCUBA dived quite a bit. I also ride motorcycles when I'm living in a country that it's safe to do so.
Explanation:
I lived in Palmdale during the Northridge quake, was in Oirase Japan during the 2011 earthquake and tsunami, went through several hurricanes in Florida and Virginia, a typhoon or six in Okinawa, wildfires in CA and TX, many tornadoes in TX, riots in CA, and I'm a Marine and USAF vet, saw the military from the POV of an enlisted Marine and a USAF officer. I've also seen blizzards, and snow in Cairo! I earned my private pilots license for rotorcraft in 2008 with plans to someday finish out my commercial license but I have mouths to feed now, am working on my divemaster certification here in Egypt, and have been riding since 2007. Actually, a huge chunk of that has been in the last 10 years.
I'm not even 40 yet.
Tsunamis are the most terrifying. You don't know when the water will stop rising. You know if you can't get high enough you are likely dead. I had a 2 year old kid with me at the time the sirens went off. The power was out and the phones were dead. Just had to wait. We lost two fishermen in Misawa and the wave fucked up Hachinohe pretty bad but where our house was was high enough. Earthquakes aren't too bad if you're in a good building, wildfires either if you just evacuate. Hurricanes aren't too scary. Move. Wait. Rebuild. Tornadoes are pretty scary. Riots trump any natural disaster, I hate large groups of people and probably will never be comfortable in crowds again.
I still like flying helos over diving, though I love diving and it's much cheaper to do. I enjoy riding, but I'm not obsessed with it. It was just a super cheap and fun way to get around when gas was ridiculously expensive.
I miss the Marines, even though most of the time it was shitty. That family is something I miss being around. I don't miss the USAF, other than the people. The people were great, the culture is shitty.