Firstly, CSO/ISO talk is strictly forbidden.
Secondly, There is a PSP programmer called Dark_AleX, who writes custom firmware. His custom firmware allows you to run homebrew and illegal material through the memory stick + having the latest firmware features. You can download the easy installer of his latest custom firmware '3.40 OE-a' Here
To install this, you need to copy the eboot folders into ms0:\PSP\GAME\

3.40 OE-a is compatible with everything Sony has to offer, so you can basically have the best of both worlds!

Lastly, you can download practically every bit of homebrew created here.

Most people are excused the first time they talk about illegal content, but the next time you could get banned; So take my warning. My e-mail is written in my signature, so contact me via that if you have any questions...

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