Well, here it is. A password protection program for the PSP. After a coldboot it automatically boots a password Program. There is no way to exit the program without the password. That's why that as of now, there is no way to change the password. I have left this out for pretty good reason. But if there is enough feedback about it, I will add it in. The universal password is 8314. Note that this REQUIRES 1.5 to get the full functionality. If you have a custom firmware, you MUST remove it as this program requires a certain custom firmware. After removing it, run the three flashers that come with the download. You may delete them afterwards except keep the config file flasher, as you might need it later.
*You are using this at your own risk. I am not responsible for ANY damages. Although I have personally tested this on my PSP, there is a chance something could happen. It's not my fault.*
UPDATE: I have attached an UN-flasher for this. It removes the custom firmware, the EBOOT.PBP and the config.txt. It's a slightly modified version of Slasher's custom firmware remover. Thanks Slasher. REMEMBER, use at your own risk!
THIS CAN NOT WORK ON 2.71 SE-B" SINCE I DON'T HAVE THE SOURCE.