Start up your PS3 and JailBreak it (BLACK B0X)- or what ever jailbreak you use...
Start up PS3 FTP Server on your PS3 and click "Start FTP Server"
Once the server is started, go back to your PC and open FileZilla
On FileZilla, click "File -> Site Manager -> New Site"
Look at the IP Address on your PS3; this will be the "Host" for FileZilla
On FileZilla, the port you will use is 21
The username you will use is FTPD12345
The password you will use is blank (no password at all)
At the top of the configuration window on FileZilla, click "Transfer Settings"
Check the box "Limit number of simultaneous connections'
Set the value to "1"
Click connect and you should be connected directly to your PS3's HDD.