Nuclear suicide...sounds fun. If I ever find myself in a situation where I want to kill myself, I might as well take out an entire city with me, and grotesquely mutate the survivors for centuries to come, spreading fallout over the land. Nothing says "I have no reason to live, and you shouldn't either" quite like a mushroom cloud.
Alien invasion...
Ever heard of sarcasm?That`s stupid. We will never get invaded by ALIENS....