Alright so Today I'll be showing You How to Unlock Everything in Split-Screen on Mw2 for Ps3, Now this does only work for Split Screen so yeah. Make sure your USB is plugged into Your Ps3. Load Up Mw2 and Go to Split-Screen. Create an Account, doesn't have to have a specific Name just do it and save that Account. Now Quit the Game and Go onto the Main Menu of the Ps3 and head over to Game. Click Save Data Utility (PS3) And Copy the Account you saved from Split-Screen to Your USB Flashdrive. Then take out Your USB Flashdrive and put it in Your Computer. Locate your USB and Open it Up and Find your Save Games. Open up Your Account and Delete the MP DATA and Replace it with this One: Just drag this into there then SAFELY REMOVE YOUR USB. Meaning right click on Your USB and click Eject. Next go back to Save Data Utility (PS3), then go to your USB Flashdrive and Copy the Account you Made. It will ask if you'd like to overwrite the file click yes. then Load Up Mw2, Go to Split Screen and Load up your Account then TA DA! All Camos, Emblems, Titles, Weapons, Attachments etc. will be Unlocked<3. All Credits goes to LifeAsANoob (His YouTube Channel).

Heres a Video for Proof made by LifeAsANoob:

Yes this was Posted on Dec 29 2009 but it still worked for Me