One of my most used plugins — RemoteJoyLite — has been adapted to the latest in custom firmwares. This plugin lets you output your PSP screen, over USB, to your Windows PC. It’s especially useful when recording gameplay, whether that is homebrew or actual PSP games.
In order to use RemoteJoyLite you’ll need the “PSP Type B” USB driver. You can find that in this package. Download, unzip, and look in the “windows” directory; there are two drivers, one for 32 bit and the other for 64 bit (x64) versions of Windows.
The rest is pretty straightforward: Activate the plugin under game.txt and/or vsh.txt, connect the PSP via USB to your PC, and start the RemoteJoyLite GUI (exe)