Nazi Zombies
We all know how annoying those zombies can get once you have reached lv 11 onwards so here's a little tip.
When you reach level 5 open the help (or hell I can't really read it properly) door and use the mystery box in the left hand corner.
Eventually you may get a flamethrower or a ray gun (preferably flamethrower) when you do get the flamethrower open up the stairs in the hell (help) room and go into the room with one window where the grenades are.
When you are in there sprint towards the grenades and jump crouch (jump then while in mid air hit B) if done properly you should end up in a glitch (which only one person can use) which shouldn't let you stand up it will keep flashing can't stand here. When the zombies pour in they will just be walking to a certain point in front of you so you can fry em with the flamethrower and if you get bored spam grenades as long as you don't move out of the spot you should be fine. It is best to do this when you have 2 or 3 others with you because the zombies go for them leaving you to gain a stupid amount of kills and point.
Hope this helps you Nazi zombie killers out there.
If you need more help, we've got more Call of Duty: World at War cheats and also check out all of the answers for this game