Here is a simple but working FTP server for the PSP.
With it, you can send/retrieve files to your PSP without any cables, in Wireless (WIFI).
It is based on psppet's networking example ported to PSPSDK.

Usage =
Wireless network must be configured properly in PSP's OS. Infrastructure mode only.
IP adresses must be static. The first network on the list will be picked. Launch the
FTPD server like any other homebrew.
Wait till it says 'Connected'.
Launch any ftp client on your PC pointing to the address shown on the psp screen.
The user is: pspkrazy
The pass is: pspftp
You're done (see What you should know).
What you should know

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