The world is a scary place, teeming with awful diseases that range from old favorites, like tuberculosis and leprosy, to terrifying newcomers, like SARS and necrotizing fasciitis. But they've got nothing on the super-bugs that filmmakers have cooked up. Just keep telling yourself, "It's only a movie, it's only a movie, it's only a movie..."

Trixie, The Crazies
A plane crash near the small town Evans City, in Pennsylvania, unleashes a psychotropic biological weapon developed by the military and code-named Trixie. It turns ordinary folks into raging psychopaths who rape, kill, or destroy everything in their paths. And if that sounds bad, the official response is no picnic, either: finding a cure takes a distant second place to making sure no one ever finds out about this major snafu.

Emmanuel, Thirst
Emmanuel appears out of nowhere and condemns its victims to a lingering, painful death, marked by grotesquely blistered skin and blood-streaked vomit. Eek! But when a saintly priest volunteers for a desperate experiment that stands a small chance of producing a cure, he comes away a vampire. Can you say, "The cure is worse than the disease"? But them's the breaks when you're fighting deadly movie pathogens.

Reaper, Doomsday
This Ebola-like virus has a twofold destructive potential. The virus is only the beginning: once it's done wiping out most of the population, the survivors devolve into Mad Max-style savagery. Pity the fools charged with going in and finding folks whose natural immunity might produce a vaccine.

Krippin, I Am Legend
Dr. Alice Krippin is trying to create a cure for cancer by tampering with the virus that causes measles but, instead, whips up a pathogen that kills 90 percent of the human race and turns the rest into weird vampire- and zombielike hybrid creatures, hell-bent on getting Will Smith and his cute dog. Oops -- but at least her name goes down in history for something. That's the dream, isn't it?

Rage, 28 Days Later...
Another bioengineered Ebola-esque contagion spread through contact with tainted body fluids. The aptly named Rage turns victims -- the Infected -- into mindless, all-but-unstoppable killers. All hell breaks loose when animal-rights activists accidentally unleash it on the U.K., during a raid on an animal-testing lab. Everything turns out okay (at least, in the original ending) -- well, unless you count half of England being annihilated as an unacceptable result.

T-virus, Resident Evil
Developed by the multiarmed Umbrella Corporation in the Hive, a top-secret underground research facility, the T-virus is a bioweapon that destroys every cell in the body of anyone unfortunate enough to be exposed. The company's security protocols can't contain the infection when it's accidentally set loose, creating zombies, undead doggies, and mutant monsters called "lickers." On the bright side, it gives Milla Jovovich a very good reason to kick some undead ass.

Chimera, Mission: Impossible II
Named for the grotesque mythological monster that melds bits of lion, snake, and goat into an unnatural horror, the Chimera virus is cooked up by Biocyte Pharmaceuticals, for the purpose of creating a market for a vaccine called Bellerophon. Chimera's symptoms -- swollen glands, bloody vomit, necrotic skin, and vicious pain -- resemble those of the bubonic plague, which killed a third of fourteenth-century Europe. Bellerophon is sounding pretty good right around now, isn't it? Evil corporate mission accomplished.

Motaba, Outbreak
And, yes, yet another Ebola-like virus -- it must be that bleeding-from-every-orifice thing filmmakers can't resist. This one makes its way from Africa to the United States, via a cute little monkey; next thing you know, it's ripping through California, with Dustin Hoffman in hot pursuit. Outbreak was indirectly inspired by the 1994 nonfiction book The Hot Zone, which, briefly, put the fear of God in folks who'd never even heard of hemorrhagic viruses or given a thought to global pandemics in the age of cheap international air travel.

Andromeda, The Andromeda Strain
Perhaps the most famous movie strain hitches a ride from outer space on a military satellite and kills every living soul in Piedmont, Arizona, by turning their blood to powder -- everyone except a little baby and an old drunk. (Perhaps confirmation that alcohol is great for you, after all.) If scientists don't find a cure fast, the whole human race will be dust in the wind. Somehow, a mutation in the virus itself fixes the problem. Go figure.

Virus Omega, On Her Majesty's Secret Service
Admit it: you had no idea that the one James Bond movie starring that other guy (George Lazenby) involved biological weapons. Created by James Bond's number-one nemesis, Ernst Stavro Blofeld, Omega is designed to be spread by a bevy of brainwashed beauties and sterilize every living thing on earth. Bye-bye, food chain; hello, Soylent Green-ish nightmare.