In Call of Duty: Modern Warfare for the PC, PS3, Wii, and Xbox 360, there are several attachments for your weapons that you unlock as your progress through levels.
Here are the attachments you can unlock, how much they cost, and what level they unlock at.
Scope Attachments
Holographic Sight – $1000, unlocked by default
Red Dot Sight – $750, unlocked at level 7
ACOG Scope – $1250, unlocked at level 30
Under-Barrel Attachments
Grip – $750, unlocked at level 19
Grenade Launcher – $1500, unlocked at level 28
Shotgun – $1500, unlocked at level 45
