Is there such thing as a popup/screamer virus?

I dunno why, but I'm absolutely TERRIFIED of those screamer things. Like, I SCREAM and can't stop shaking for hours. I go so insane. Now I have this paranoia that theres gonna be a screamer virus on my computer and it will just randomly pop up. I'm sitting here in my dark bedroom being scared.... Is there such thing? Is it preventable?