The following are known Gecko Codes for Call of Duty: Modern Warfare 3 on Nintendo Wii (Wii).

Purple And Green Vision [Crashzer]
F6000001 80008100
3C800000 00000000
14000014 FF00FF00
E0000000 80008000

Dark Blue And Yellow Vision [Crashzer]
F6000001 80008100
80A30008 7FE3FB78
143697D4 0317FC00
E0000000 80008000

Grey And Bronze Vision [Crashzer]
F6000001 80008100
7C850050 4802840D
143697C4 020067F0
E0000000 80008000

Campaign Codes (Press Home on Campaign to activate)

Unlock All Missions [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
80040004 7C1F00AE
F4000004 00000003
2C000571 4082000C
38000012 7C1F01AE
7C1F00AE 00000000
E0000000 80008000

Infinite Ammo [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
7FE5FB78 7CDE00D0
F4000004 FE849D01
38C00000 60000000
E0000000 80008000

God Mode [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
933F003C 933F0040
F4000034 022C0002
38000001 981A014F
801A0160 00000000
E0000000 80008000
*Demo Video: http://www.youtube.com/watch?v=NtLWNA8XWLE

Attack Team Mates [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
801F031C 60000008
F4000004 02930301
60000000 60000000
E0000000 80008000
*You will not be prevented from knifing/shooting your team mates on purpoise*
*This does not bypass the "Friendly fire will not be tolerated" message*

Moonjump [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
C01D002C D0010094
F4000008 02D09904
3D808020 A18C236A
2C0C0008 4082000C
3D804450 919D0030
C01D0030 00000000
E0000000 80008000
*Press D-PAD UP on Wiimote to moonjump*

Sticky Grenades [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
806B03E0 88030008
F4000004 022C0001
38000000 60000000
F6000001 80008100
EC400032 C01A0018
F4000198 02FC4102
3D804CBE 91830008
C0030008 00000000
E0000000 80008000
*Frags will stick to the ground if thrown, but still bounce off walls*

Hide Ammo Counter [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
901F0000 2C830000
F4000020 02901B01
38000001 60000000
E0000000 80008000

No Heads-Up-Display (HUD) [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
7C850214 3C640002
F4000054 022C0001
38000000 60000000
E0000000 80008000

Infinite UAV [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
60000001 901F0028
F4000010 022C0001
38000001 60000000
E0000000 80008000
*Check your pause menu map to see enemy dots*

Unlimited Sprint [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
3803FFF5 7C000034
F400008C 024EA001
38600001 60000000
E0000000 80008000

Movement Speed Modifier [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
80010184 901F0058
F4000010 02904301
3800XXXX 60000000
E0000000 80008000
*XXXX Values*
0064 = Slow Speed (100)
00BE = Default (190)
015E = Super Speed (350)

Field of View Modifier [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008000
7C9C2378 FFC00890
F4000028 013C6002
3D80XXXX 91830008
C3E30008 00000000
E0000000 80008000
*XXXX Values*
4248 = Lesser FOV (50)
4282 = Default FOV (65)
42A0 = Higher FOV (80)

Pause Menu Map Size Modifier [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
C0040008 EC010032
F4000000 02EC3302
3D80XXXX 91840008
C0040008 00000000
E0000000 80008000
*XXXX Values*
3F00 = Little (0,5)
3F80 = Default (1)
3F9D = Bigger (1,2265625)

Gravity Modifier [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80108100
801F0148 2C000000
F4000098 013C6002
3D80XXXX 91840008
C0230008 00000000
E0000000 80008000
*XXXX Values*
4396 = Low Gravity (300)
4448 = Default Gravity (800)
44BB = High Gravity (1496)

Game Speed Modifier [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
F4000004 00000002
3D80XXXX 91830008
C0030008 00000000
E0000000 80008000
*XXXX Values*
3F00 = Slow Motion (0,5)
3F80 = Default Speed (1)
4000 = Fast Motion (2)

Cartoon Vision [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80108100
9864002A 9864002B
F400001C 022C0001
38000001 60000000
E0000000 80008000

Playtime Is 00:00:00 [Bully@Wiiplaza]
2820236A 7FFF8000
F6000001 80008100
F4000004 021F8402
38000000 90030020
60000000 00000000
E0000000 80008000

Special Ops Codes

Infinite Money [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
801E0000 901F6200
F4000004 0283FD04
2C163970 40820010
3D807FFF 919F6200
48000008 901F6200
60000000 00000000
E0000000 80008000
*This will give you 2147418112 money after getting your first kill*
*Demo Video: http://www.youtube.com/watch?v=a1tnWPZbmVc

Instant Lv. 50 [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
80650000 7CA320AE
F4000004 02669004
2C040008 40820010
3D80FFFF 618CFF00
7D83212E 7CA320AE
60000000 00000000
E0000000 80008000
*Enter Spec Ops to instantly become Lv.50, play one mission to save the hacked level*

Infinite Ammo [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
7FE5FB78 7CDE00D0
F4000004 FE849D01
38C00000 60000000
E0000000 80008000

God Mode [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
60000200 90040010
F400000C 0251EA01
38000001 60000000
E0000000 80008000
*Total invincibility against everything*
*Credits to WiiOS_Ozelot for original address*

Multiplayer Codes

Infinite Ammo [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
7FE5FB78 7CDE00D0
F4000004 FE849D01
38C00000 60000000
E0000000 80008000
*Demo Video: http://www.youtube.com/watch?v=sj9c3YipZqY

God Mode [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
80040364 7C030000
F4000024 0253BF01
38001001 60000000
F400CFB4 0253FF01
38001001 60000000
E0000000 80008000
*Total invincibility against everything*

Noclip [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
901E00F8 807E2A60
2820236A YYYYZZZZ
F4000004 02539F01
38600001 60000000
CC000000 00000000
F4000004 02539F01
807E2A60 60000000
E0000000 80008000
*You can fly around/through walls using the Nunchuk Stick*
*Press your button(s) to toggle ON/OFF*

Game Speed Modifier [Bully@Wiiplaza]
201D2644 FFFFFFFA
F6000001 80008100
806500F0 80030008
F4000040 02EC1302
3D80XXXX 91830008
C0030008 00000000
E0000000 80008000
*The higher the value, the faster the game speed*
*XXXX = Float*

Pickup range mod [Clay10]
201D2644 FFFFFFFA
F6000001 81008180
81149610 80716774
14000050 7F800000
E0000000 80008000
Host only

Infinite Ammo Spec Ops [Seth@WiiPlaza]
28XXXXXX XXXXXXXX
F6000001 80008100
80030004 7C00FA14
14000004 60000000
E0000000 80008000
*Add Your Own Custom Button Activator (X'S)
*Works Host and Publicly!!
*Demo Video http://youtu.be/OuiTMBm7euk
*Only works when you activate in a game 1 time, then after you die or restart the match, it will start to lag the host. so if you want it to work clearly again, restart your wii and reactivate.