Recently, a new piracy technique on PS4 in Brazil confirmed to be real.

The following tutorial shows you how to register the flash memory to allow account sharing. I didn't tested this tutorial, thus is for information purposes only.

To avoid de-solder the NAND from the motherboard, see the image below how to solder the chip on Raspberry Pi.

Needed
A Raspberry Pi with an SD card
Raspbian
Win32 Disk Image
Putty

How to
Write Raspbian's image file into the SD card, by using Win32 Disk Image. After finishing the process, put the SD card into the Raspberry Pi and connect it using a USB cable (to power it up). After starting the Raspberry Pi, wait it to load the OS and run the Putty on your PC.

In the Host Name put: raspberrypi. If this does not work correctly, go to the settings of your router and find the IP of the Raspberry Pi. Select SSH and click on "Open".

You will be asked to login. Use "pi" as username and "raspberry" for the password. Now enter the following commands:

sudo -s
cd / bin
wget http://jaicrab.org/Ps4/Tools/JAISPI/jaispi
chmod + x jaispi
echo "#blacklist spi-bcm2708"> /etc/modprobe.d/raspi-blacklist.conf
echo "blacklist i2c-bcm2708" >> /etc/modprobe.d/raspi-blacklist.conf
reboot

After rebooting, run Putty again and now enter the commands below. You will get some options:
# sudo -s

Jaispi -i / dev / spidev0.0

The options are:
-i /dev/spidevX.X (Get the flash ID)
-r file.bin /dev/spidevX.X (Read all the flash of a file)
/dev/spidevX.X -e (Deletes all flash)
-p file.bin /dev/spidevX.X (Records only the different blocks of a file)
-v file.bin /dev/spidevX.X (Check the blocks of a file)

Get flash information

Command -i displays information about the flash.

Use:
#jaispi -i /dev/spidev0.0
JaiSpi v1.0
ID: 0xC22019 MX25L25635

Make a full dump of the flash

Command -r makes a full dump of the flash (It takes about 35 sec)

Use:
#jaispi -r DUMP.bin /dev/spidev0.0
JaiSpi v1.0
ID: 0xC22019 MX25L25635

You will get this message:
Reading ...
0x02000000
Done!

Clean the flash

Command -e cleans the flash (It takes around 1 and a half min)

Use:
#jaispi -and /dev/spidev0.0
JaiSpi v1.0
ID: 0xC22019 MX25L25635

You will get this message:
Erasing blocks ...
Done!

Write the flash

Command -p writes in flash only the changed sectors (It takes around 1min 30sec)

Use:
#jaispi -p Base.bin /dev/spidev0.0
JaiSpi v1.0
ID: 0xC22019 MX25L25635

You will get this message:
Starting ...
0x02000000 -> 8192 written Sectors
Done!

Check the flash

Command -v compares the flash content (It takes around 35sec)

Use:
#jaispi -v Base.bin /dev/spidev0.0
JaiSpi v1.0
ID: 0xC22019 MX25L25635

You will get this message:
Checking ...
0x02000000 -> 0 Different sectors
Done!

Given the complexity of the operations and the lack of details, i suggest to avoid trying this method and wait for a simpler one.