If you want to look on the brighter side consider the optimism of Warren Buffet. He insures a substantial slice of the world's risk so it's his job to rational

If you want to look on the brighter side consider the optimism of Warren Buffet. He insures a substantial slice of the world's risk so it's his job to rationally assess looming disasters. He's not particularly worried at this point so you probably shouldn't be either. On the other hand, if you prefer the doom and gloom you might want to add a possible asteroid impact to your list. The dinosaurs had one and it really was the end of the world for most of them.