The sprinting savages: '28 Days Weeks'

For the longest time, we had one advantage over the undead: They were really, really slow. As long as you could race walk, you could probably outpace the things that want to snack on your cerebellum. Then came '28 Days Later' and '28 Weeks Later.' These zombies can move. OK, fine, they're not undead, and therefore not really zombies -- but they're still scary as hell.