Zombies Ate My Neighbors Cheats for SNES
To go to a secret bonus level, enter BCDF or GYLM.
To access a different secret level, listen up. Type in the code to go to level 9
(WBGR) and play through the next 4 levels without letting any of the victims die. As soon as you rescue all of the victims in level 12, you'll automatically go to a bonus level as soon as you walk through the exit door. Also, you don't have to enter the level 9 password, instead you can play all the way through it, but in the long run, it helps.
No thumbs
yet
If you want to hear some cool stuff, listen up.
When you start up the game, at the Lucas Arts logo, press "L" or "R" to hear a cool sound. Both of these buttons make a different sound from the other, so try them. If you want to view the credits with beating the game, type in XWJR in the password screen, and you should be able to view them.
No thumbs
yet
Under the password screen, you can type in these codes to choose your level.
I do not believe these are all of them, but here's a good chunck.
Level 2 = PHZB
Level 4 = XHRS
Level 5 = FHRX
Level 6 = PHRP
Level 8 = WBGR
Level 9 = NBGW
Level 12 = GFCY
Level 13 = FRCR
Level 16 = KKYM
Level 17 = RKYL
Level 19 = DBJK
Level 20 = BXBS
Level 21 = PXBG
Level 24 = GYLM
Level 25 = XYLZ
Level 28 = GLZJ
Level 29 = XLZG
Level 32 = XJQY
Level 33 = WJQK
Level 36 = KZVJ
Level 37 = BZVG
Level 40 = KRPY
Level 41 = BRPK