GTA 4

Get Full Health and Weapons:
Call GTA-555-0100 (482-555-0100) on your phone. (Blocks the Cleaned the Mean Streets achievement)

Get Weapons:
Call GUN-555-0150 (486-555-0150) on your phone. (Blocks the Cleaned the Mean Streets achievement)

Get Advanced Weapons:
Call GUN-555-0100 (486-555-0100) on your phone. (Blocks the Cleaned the Mean Streets achievement)

Get Full Health:
Call DOC-555-0100 (362-555-0100) on your phone. (Blocks the Cleaned the Mean Streets, Finish Him, One Man Army & Walk Free achievements)

Wanted Level Down:
Call COP-555-0100 (267-555-0100) on your phone. (Blocks the One Man Army & Mean Streets achievements)

Wanted Level Up:
Call COP-555-0150 (267-555-0150) on your phone.

Change Weather:
Call HOT-555-0100 (468-555-0100) on your phone.

Spawn Cognoscenti:
Call CAR-555-0142 (227-555-0142) on your phone.

Spawn FBI Buffalo:
Call CAR-555-0100 (227-555-0100) on your phone.

Spawn Turismo:
Call CAR-555-0147 (227-555-0147) on your phone.

Spawn Comet:
Call CAR-555-0175 (227-555-0175) on your phone.

Spawn SuperGT:
Call CAR-555-0168 (227-555-0168) on your phone.

Spawn NRG900:
Call MBK-555-0100 (625-555-0100) on your phone.

Spawn Sanchez:
Call MBK-555-0150 (625-555-0150) on your phone.

Spawn Police Chopper:
Call FLY-555-0100 (359-555-0100) on your phone. (Blocks the One Man Army & Walk Free achievements)

Spawn Jetmax:
Call WET-555-0100 (938-555-0100) on your phone.