First-person-shooters (FPS) as a genre are not going away anytime soon. Whether that makes your eyes roll so far back into your head you're looking at your brain stem, or makes you think about calling out sick to go up your gamer score on Xbox Live says a lot about what side of the gaming divide you fall on.

So, if your pupils aren't getting acquainted with your gray matter right now, we've got an awesome list for you. Here are the 50 Greatest First Person Shooters of All Time, loaded, cocked, and ready to fire. Guns up!